CHAPTER-4

ELEMENTARY STUDENTS’ CONCEPTIONS ABOUT FOOD AND NUTRITION

4.1 Introduction

4.2 Scientific Evolution of the Concept: Food and Nutrition

4.3 Pedagogical Perspective of the concept: Food and Nutrition

4.4 Development of the Concept Maps: Food and Nutrition

4.4.1 The Intended Concept Map: Indian Source

4.4.2 The Intended Concept Map: International Source

4.4.3 The Derived Concept Map: Food and Nutrition

4.5 Students’ Conceptions of Food and Nutrition: Primary Source

4.5.1 General Analysis of Students’ Conceptions about Food and Nutrition

4.5.2 Comprehensive Analysis of Students’ Conceptions about Food and Nutrition

4.5.2.1 Students’ Conceptions about Food and Nutrients

4.5.2.2 Students’ Conceptions about Digestion

4.5.3 Discussion

4.6 Conclusion

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CHAPTER-4

ELEMENTARY STUDENTS’ CONCEPTIONS ABOUT FOOD AND NUTRITION

4.1. Introduction

Food is the source of energy and matter for all organisms and is one of the

links between them. The way we use the term food in everyday language

depends on the context. Text books used in schools describe food in a variety

of ways. There is a lack of an agreed definition of food by scientists (Barker,

1985, as quoted by Francis and Hill, 1993). Food as a concept is fraught with

the semantic problem of the word food having different meanings in everyday

and scientific contexts (Driver et. al, 1994). The school science definition of

food, as organic compounds, which organisms use as a source of energy for

metabolic processes, is not consistently used by science educators. Some text

book authors consider water as food since it has minerals, some do not since

water is not organic. Nutrition is the process by which living organisms obtain

food and use it for growth, metabolism and repair. The stages of nutrition

include ingestion, digestion, absorption, assimilation and excretion. Food

provides matter and energy to the plants and animals and is the link between

inanimate things like gases, minerals, water etc and the living world. Food and

nutrition is an important component of Biology linked with Human Physiology,

Ecology, Nutrition and Dietics and other similar subjects.

The concept of food and nutrition is introduced from early elementary classes

and even to pre-primary children since it is integrally linked to our well-being

and health. While the sub concepts of variety of food, healthy food and junk

food, hygiene, healthy food habits are part of primary classes; components of

food, role of various nutrients in human body, plant nutrition, digestion and

nutrition in animals (humans), management of food resources etc are part of

upper elementary curriculum.

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The following section traces the evolution of the concept of food and nutrition

historically from the time of Hippocrates.

4.2. Scientific Evolution of the Concept: Food and Nutrition

The concept of Food and Nutrition has been evolving since 400 BCE when

Hippocrates said that food has a positive effect on our health and well being.

But the major ideas evolved since mid of eighteenth century till the present.

Around 1770, Antoine Lavoisier, the “Father of Nutrition and Chemistry”

discovered the details of metabolism demonstrating that the oxidation of food is

the source of body heat. In 1790, George Fordyce recognized calcium as

necessary for fowl survival. In the early 19th century, the elements- carbon,

nitrogen, hydrogen and oxygen were recognized as the primary components of

food, and methods to measure their proportions were developed.

In 1816, Francois Magendie discovered that dogs fed only with carbohydrates

and fat lost their body protein and died in a few weeks, but dogs also fed with

protein survived, identifying protein as an essential dietary component. In 1747,

Dr. James Lind a physician with British Navy discovered that the sailors who

were given limes were saved from scurvy while others suffered. Vitamin-C was

discovered much later in 1930’s as a vital nutrient. It was discovered in early

1800s that food is composed mainly of four elements: carbon, hydrogen,

oxygen and nitrogen. J. Leibig of Germany was the first to point out chemical

makeup of carbohydrates, fats and proteins in 1840. One by one all vitamins

were discovered in early 20th century. Since 1950s to the present, the role of

essential nutrients as part of bodily processes has been brought to light.

Fibre became a household word back in 1970s when Dr. Denis Burkitt, a man

nicknamed the Fibre Man, and his colleagues made “the fibre hypothesis” that

states that fibre can prevent certain diseases. Through their work in Africa, they

discovered that diseases that were common in the Western cultures were not

common there. These included heart attacks and high blood pressure

(cardiovascular diseases) obesity and diabetes (metabolic disorders), intestinal

problems (constipation, gallstones, appendicitis and colon cancer), varicose

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veins and blood clots (deep vein thrombosis). The primary dietary difference

was the high intake of fibre and low intake of refined carbohydrates in the

African population. Burkitt also noted the emergence of these diseases in the

United States and England after 1890 following the introduction of a new milling

technique that removed fibre from whole grain flour to produce white flour. More

became known about the role of vitamins and minerals as components of

enzymes and hormones that work within the body. Synthetic enzymes and

vitamins were synthesized.

The idea about human nutrition kept evolving since the ancient anatomists.

Ancient and medieval anatomists had fairly accurate gross physiological

knowledge of the structure of stomach, intestines and colon. They recognized

the importance of digestion as a key aspect of maintaining the humoral balance

of the body. Initially medical practitioners viewed the stomach as an active,

almost thinking agent in the body. Galen additionally described it as a store

house of nutrition that sorted the ‘wheat from the chaff’ meaning that stomach

has a filtering effect also. In the Galenic tradition, it was the site of first

digestion, since the body digested nutrients in multiple ways. Every aspect of its

shape and texture – even its location – facilitated this process. Master Nicolaus

in the twelfth century poetically wrote: “The stomach has the liver below it like a

fire underneath a cauldron; and thus the stomach is like a kettle of food, the

gall-bladder its cook, and the liver is the fire.” Similarly, the names of parts of

the digestive system recalled their specific functions. Many thought that the

colon was a colander that strained the faeces.

Increased dissection led to more detailed descriptions of the organs involved in

digestion and illustrations were drawn of the organs and their internal

structures. Leonardo da Vinci believed that the digestive system aided the

respiratory system in its function. In the mid-seventeenth century, a Flemish

physician Helmont offered the first chemical account of digestion and placed

emphasis on the stomach as a chemical laboratory (known as alchemist theory

of medicine).

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By 1825, Dr. Beaumont began to experiment on digestion using an open

wound in the stomach of St. Martin, a wounded soldier. Dr. Beaumont worked

on the samples of stomach to digest bits of food in cups. This established that

digestion was primarily a chemical process and not a mechanical one. In 1835,

German physiologist Theodor Schwann discovered the non-acidic component

of gastric juice which he named pepsin (to digest’ in Greek) which was later

shown to be an enzyme. In 1897, another German scientist, Eduard Buchner,

discovered by accident that fermentation actually does not require the presence

of living yeast cells. Buchner made an extract of yeast cells by grinding them

and filtering off the remaining cell debris. Then he added a preservative-sugar

to the resulting cell-free solution to preserve it for future study. He observed that

fermentation, the formation of alcohol from sugar, occurred. Buchner then

realized that living cells were not required for carrying out metabolic processes

such as fermentation. Instead, there must be some small entities capable of

converting sugar to alcohol. These entities were enzymes. Buchner’s accidental

discovery won him the 1907 Nobel Prize in Chemistry.

Thus, scientific methods of inquiry, imagination of brilliant minds, in addition to

discovery of technological instruments have helped humanity develop an

understanding about food and nutrition (Refer to figure 4.1).

From the timeline of food and nutrition, it is understood that evolution of food

and of nutrition occurred independently. Evolution in food and digestion

stemmed from speculation: speculation about effects of food with health,

speculation about role of different organs or glands in the body. Interpretation of

observations of experimentations leads to generalisations such as those of Dr.

Beaumont. From the study of the evolution of food and nutrition, the

implications for school science is that alternate conceptions of students are

important starting points for subsequent scientific understandings. Students

may comprehend generalisations about food and nutrition from explanation of

experiments and subsequent theory-building. Learners would probably

understand and describe concepts related to food first, and then understand

nutrient of food. Explaining or emphasising the need of including a component

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or nutrient into diet may not useful for learners till they comprehend the

biochemical nature of its transformation inside the body. Hence the attention of

students also needs to be drawn to conceptual explanation behind chemical

transformation of food, absorption and assimilation.

Fig. 4.1: Time Line – Food and Nutrition

4.3. Pedagogical Perspective of the Concept: Food and Nutrition

Food and digestion is a topic fundamental to most science curriculum and a

core concept of living things. Digestion relates to other major life processes

Food and Nutrition

400-BC-Hippocrates-food has

positive effect on our health

1567-Helmont-Given an account

about digestion

1651-Harvey-Living things

Originate from eggs.

1747-James Lind-

Discovered Vitamin C

1770- Antoine Lavoisier-

Became father of nutrition

and Chemistry

1790- George Fordyce-

Recognized calcium

Francois-1816- Invented

the importance of dietary

protein

1840-J.Leibig- Chemical

makeup of carbohydrates

1897- Eduard Buchner-

invented enzyme

1905- William Fletcher- Identified the

role of essential nutrients Dr. Denis Burkitt- Invented

fibers and its use full ness

for good health

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such as respiration, circulation, excretion and growth. Therefore teaching of this

concept requires particular attention in science education. Food, eating and

digestion are inter-related concepts and curriculum places emphasis on the

development of knowledge and attitudes in school children that are conducive

to healthy nutrition and living.

The historical evolution of the concept of food and nutrition has shown that a

complete understanding of nutrition is an ongoing endeavour on the part of the

scientific community comprising of nutrition specialists, molecular biologists,

medical practitioners, chemists among others. Sophisticated concepts of food

and human nutrition have emerged as part of interdisciplinary research. The

discovery of various aspects of food and nutrition over the human history has

helped humans have a cogent area of knowledge about human nutrition.

Though new discoveries are being made about the role of enzymes, or proteins

or other bio-molecules, they are at the ultra-cellular and at times sub-atomic

level and pertain to medical sciences and not the science teaching till

secondary level per se. Understanding the pedagogical aspect of the concept

of food and nutrition would help the researcher to build a more complete

comprehension of the difficulties if any in the understanding of the concept by

elementary students and to finalise the conceptual statements based on which

questions would be framed. Much of children’s ideas about food and digestion

have been compiled in the research summary developed by Leeds National

Curriculum Science Support Project, 1992 with the aim to help teachers.

Pedagogical perspective has been collated from the above summary and other

research conducted by nutritionists, and other researchers from the perspective

of science education or child development.

Children and most adults consider food as that which is fit for human

consumption; i.e, food is something which is eaten. They usually extend it to

mean anything useful taken into an organism’s body, including water, minerals.

From an early age, children seem to know that eating has many consequences:

growth, health, strength and energy. From the age of eight, most children

differentiate different kinds of diets as making people fat or strong. Contento

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(1983) found that children in concrete operational stage can classify concrete

items such as foods into groups and understand that food is changed in some

way in the stomach, but they do not know how the effect was brought about.

In the everyday context, children and most adults think food as something we

eat. Food is thought of as solid and not drinks/beverages. Learners identify

food as material to provide growth, health and activity. They do not recognise

that food is source of material to become part of their bodies in growth or that

food is source of energy. Children( 5 to 11 years) do not refer to a transfer of

matter from the environment to the organism, though some children do explain

the growth of animals by stating that the organism has to ‘stretch’ to make room

for the food eaten( Russell and Watt ,1989). Smith and Anderson (1986)

suggested that many 11 to 12 year olds conceptualise food as something that

can be created and destroyed, and converted directly into energy. According to

Barker (1986), older secondary school students’ use of edibility and palatability

as criteria of food gets replaced by the energy criterion. The benefits of eating

food to organisms are seen as an example of cause-effect reasoning rather

than as a transformation of matter from one form to another.

From an early age, children, know that what we eat consists of proteins, fats,

vitamins etc, but they do not understand function of these substances and do

not recognise them as groups of materials. They do not distinguish the food we

eat from the components, for example, they have the notion that bread is

starch, pulses are protein etc. They may not understand the cellular or

molecular nature of food (Simpson, 1984).

Young children have various notions about their body parts like stomach and

digestion of food .They imagine their body to be hollow bag, which is all

‘stomach’ containing food, blood and wastes (Gellert, 1962). The youngest

children relate the stomach to breathing, blood or strength and energy. From

about seven they begin to know that the stomach helps to break or digest food,

and later that food is transferred elsewhere after being in the stomach and by

age 9, most children listed several organs including the stomach. Older children

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realise that there is a food bag inside the body, but use ‘stomach’ to apply to

both stomach and abdomen. Gellert, 1962 found that by 11, most children had

a fairly correct outline of anatomy and the overall function of systems. She

attributed the initial ideas to sensations of heartbeat and swallowing, and later

ideas to TV and hospital experience. Many think that digestive system has two

outlets, one for feaces and one for urine.

A very common concept amongst children is that digestion is the process which

releases usable energy from food. This arises from linking the two acceptable

ideas ‘energy’ is obtained from food’ and ‘digestion is the breakdown of food’ to

construct an unorthodox idea.

Simpson (1984) found that at thirteen, children’s ideas of the sequences of

digestion are very confused, both in terms of the anatomical route and the

processes. Routes may include the trachea, heart, kidneys in some children’s

minds. The sequence of processes may start with breaking into soluble

particles, releasing energy, followed by swallowing. These ideas are not naïve

intuitive notions but construction derived from an overload of information. Pupils

have been taught a lot of unfamiliar words or familiar words in a new context.

Leeds National Curriculum Science Support Project (1992) researched and

reviewed existing research into children’s ideas about nutrition and concluded

that the challenge for elementary students is to accept that digestion is not an

end in itself but an intermediate stage between eating and building new body

substances or releasing energy. The challenge can be tackled at two levels: (1)

working and refining everyday words connected with digestion into scientific

meanings. (2) for a deeper level understanding, developing the concepts of

conservation of matter and matter being rearranged. Further, understanding of

digestion depends on previously established concepts of solids, liquids and

solubility.

Assimilation of food is central to understanding much of biology (Driver, 1994).

Conceptual understanding in most aspects of nutrition would be achieved if

learners understand that what we eat actually becomes skin, bone, blood etc

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(and what plants make, becomes leaves, wood etc.). Understanding bio-mass

may be a useful step for learners to realise that bio-mass consists of products

of chemical interactions and may act as reactants in further chemical

interactions. Once learners have developed particle ideas, they may be able to

integrate assimilation with rearrangement of atoms.

Table 4.1: Investigators Studying Conceptions of Elementary Students about various Food and Nutrition Concepts

Sub-concepts of Food and Nutrition

Investigators

Below 9

yrs

4th

(9 yrs)

5th

(10 yrs)

6th

(11 yrs)

7th (12 yrs)

8th

(13 yrs)

Nutrients in Food Arnold and Simpson (1980)

Food-Concept Barker (1985) � � � � �

Consequences of food Carey S. (1985) � � �

Food – source of energy Leach, Driver et al. (1992)

� � � � � �

Food-source of energy Francis and Hill (1993)

�

Classification, importance of nutrients

Sheila Turner (1997) � � �

Nutrients and health Dixey, Sahota et al. (2001)

� � �

Food groups, nutrients & health

Hart,Bishop and Truby (2002)

� � � �

Digestive organs and their role

Gellert (1962) � � � � � �

Enzymes egestion Simpson (1984) �

Respiration & digestion Nunez and Banet (1997)

� � �

Structure & function of D.S Texeira (2000) � � �

Digestive system Reiss and Tunnicliffe (2001)

� � � � � �

Digestion process,circulation

assimilation Carvalho (2004) � � �

Digestion process Cakici Y. (2005) � �

Digestive system-figure Mathai and Ramadas (2009)

� � �

Digestive system & respiratory system-figure

Susana Gracia-Barros et al. (2011)

�

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Researchers have researched into students’ conceptions of food and nutrition

using techniques and tools according to various perspectives starting from pre-

primary children to adults (Table 4.1). From all the available research in the

area of elementary students’ understanding of food and nutrition concepts, one

can infer that research on food is a strand separate from the nutrition strand.

Mostly researchers have investigated in either of the strand. Researchers have

investigated on the sub-concepts of meaning of food as perceived by learners,

classification into food types, importance of nutrients in our body and impact of

food on health. Within the digestion and nutrition strand, the sub-concepts

investigated are about the structure of digestive system, understanding about

role of mouth, stomach intestines etc., and concepts about assimilation,

absorption and the relation between concepts of energy, matter and digestion.

The concepts investigated with youngest children are often, meaning and

classification of food (Contento, 1983), structure of digestive system (Gellert,

1962) and children’s perceptions about nutrition and growth (Leach et al., 1992)

and conceptual understanding about relation between digestion and other life

processes are investigated of older learners (Table 4.1) .

Learners are able to relate to concepts of food easily than those of nutrients

which needs understanding about particulate nature of matter. The challenge

for elementary students is to accept that digestion is not an end in itself but an

intermediate stage between eating and building new body substances or

releasing energy. This would be progression of learners towards sophisticated/

integrated food and nutrition concepts which seems difficult at the elementary

level without pedagogical efforts directed towards that end.

Having known the conceptual resource of learners from the pedagogical

perspective about food and nutrition prepares the researcher to develop

questions to generate primary data.

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4.4. Development of the Concept Maps: Food and Nutrition

Concept maps were developed to fulfil the following objectives:

a. To understand what the intended curriculum includes in the area of food

and nutrition in Indian context

b. To identify what constitutes ‘standard’/expected knowledge in the area from

available curricular resources and

c. To derive a concept map from the maps at a) and b) above and to form a

basis for developing questionnaire

Concept maps can be defined as visual representations that are added to

instructional material to communicate the logical structure of the instructional

material. The concept map serves as a device to illustrate the hierarchical

conceptual and propositional nature of knowledge. The concepts are arranged

in a hierarchy with a super ordinate concept at the top. The concepts are linked

by lines labelled with connecting words that form the proposition uniting the

concepts. Concept mapping requires the mapper to prioritise and make

judicious use of selected concepts when mapping (Novak and Gowin 1984). It

involves identification of concepts in study materials and their organisation from

the most to least general and more specific concepts.

Concept maps are flexible tools that can be used in a variety of educational

settings (Stewart, Van-Kirk and Rowell, 1979).They have been used as a tool

for assessing meaningful learning (Novak, 1979) as well as in curriculum

planning, instruction and evaluation( Stewart et al,1979).Concept maps are

useful in science curriculum planning for separating significant from trivial

content (Starr and Krajcik, 1990) and focussing the attention of curriculum

designers on teaching concepts and distinguishing intended curriculum from

instructional techniques (Stewart et al, 1979). Science educators extract, select

and prioritize concepts from information-dense materials (Jonassen, Biessner

and Yacci, 1993). Science education reforms have developed concept maps to

decide which concepts are the most important to learn and use what are

important concepts that contribute the big picture or pervasive principles at the

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core of scientific disciplines. Science curriculum reforms in USA and Australia

are such cases and are being presented in the following paragraphs.

AAAS Project 2061 and the National Science Teachers Association (USA)

published two volumes of Atlas of Science Literacy including nearly 100 maps

which chart all the learning goals specified as ‘Benchmarks’ essential for every

student to learn. The maps given in the Atlas of Scientific Literacy illustrates the

relationships between individual learning goals and shows the growth of

understanding of ideas. Connecting arrows indicate the connections between

ideas which are based on the logic of the subject matter (or on cognitive

research about how students learn). The maps are available at

http://www.project2061.org//tools//benchol/bolframe.html.

The Department of Education and Early Childhood Development (DEECD),

State Government of Victoria, Australia has developed the science continuum

P-10 for effective science teaching. The Science Continuum P-10 identifies

focus ideas at each level of essential learning standards for science.

Connections between concepts and pathways of student’s conceptions are

mapped in science concept development maps. The concept developmental

pathways are the ones students may take when developing scientific

understandings. They demonstrate the relationship between concepts and their

contribution to a range of scientific fields and the increasing complexity

developed from more simple understandings. The concept maps are available

at www.education.vic.gov.au/studentlearning/teachingresources/science.

The development of concept maps of Food and Nutrition was taken up by

analysing (a) the Environmental Science Text books (class 3rd to 5th) and

Science Textbooks of NCERT (class 6th to 8th) and (b) International standards

in science and other curricular material available through web resources.

4.4.1. The Intended Concept Map: Indian Source

In our country NCERT is an apex body under the Ministry of Human Resource

Development (MHRD) which is responsible for preparing curriculum guidelines

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for the entire country. It also develops and publishes text books based on the

guidelines prescribed in the National Curriculum Framework. Since education is

in the concurrent list, most of the states, develop their own curricular material

based on the national curriculum framework. Some of the states adopt the

NCERT textbooks translating it in regional languages (e.g. as in case of Delhi

State) and other states adopt them to suit their local contexts. With an

experience in the field, the researcher has found that private publishers or

publishers of the state board mostly develop text books in the same lines as the

NCERT textbooks and hence NCERT textbooks were selected as symbolic

source of intended curriculum in the Indian context The syllabus guidelines for

elementary classes for environmental studies (from class 3rd to class 5th) and

science (from class 6th to 8th) were looked into. At the primary level, science is

part of environmental studies and not as a separate subject. At the upper

primary level science is taught as a compulsory subject. The textbooks from

class 3rd to 8th and syllabus guidelines of elementary classes were analysed to

derive a concept map. The syllabus guidelines and textbooks are available at

www.ncert.nic.in. After Starr and Krajcik (1990), significant content was

separated from trivial content to focus the attention on teaching concepts and

distinguishing intended curriculum from instructional techniques (Stewart et al,

1979) to draw the concept map.

The outline of the concepts and sub concepts of food and nutrition has been

drawn in the coming sections (refer to Figure 4.2). To understand the

placement and depth of the concepts in each grade, the researcher identified

the following ‘conceptual dimensions’ (Savinainen and Scott, 2002; Stevens et

al, 2009) / strands under the concept food and nutrition. Ideas that describe

concepts related to, or necessary for understanding food and nutrition were

collected and categorized within these conceptual dimensions or strands.

Because of the nature of the field, many ideas fall into multiple dimensions, but

are considered in any one dimension while analyzing.

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Fig. 4.2: Concept Map on Food and Nutrition – From Intended Curriculum: Indian Source (Developed by the Researcher)

FOOD & NUTRIENTS

Food choices/preferences,

Hunger

Sources of food: Plants-potato

and corn, animal foods, Honey,

Eggs Plants-food from leaves,

flowers, root etc.

Food: various types of

animals, goat and snake etc.

Variety of food eaten

during journey

Community lunch at

Gurudwara

Jaggery,

Amla, Leafy

Vegetables to

cure anemia

Plant parts and animal

products as food

Components of food –

carbohydrates, fats,

proteins, vitamins and their

role, deficiency diseases

DIGESTION

Teeth help in eating

Animal, Teeth and their functioning

Digestion begins in the mouth stomach

in digestion, hunger, junk food glucose

drip (Taste buds & tongue)

Animal nutrition: digestive system-

human digestion of carbohydrates,

proteins and fats by digestive

juices, digestion process –

ingestion, digestion, absorption-

assimilation-egestion

Aerobic and anerobic

respiration, cellular respiration,

food-respiration, energy

products like alcohol, water,

lactic acid or carbon dioxide

AGRICULTURAL

PRACTICES

Some food crops,

how they are grown

implements

Change in

agricultural practices

Plant nutrition: photosynthesis

heterotrophic plant nutrition,

parasites, insectivorous plant,

saprotrophs

Crop production: basic practices

implements, fertilizer and

manure management and storage

Digested food circulated

through circulation system

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The major strands under consideration are:

• Food-nutrients, micronutrients, balanced diet

• Human digestive system-parts, functions of organs, digestion process.

Each strand was traced in the context of all chapters presented in the textbooks

of Class 3rd to 8th related to food and nutrition concept.

The concepts of food and nutrition were analysed in EVS and Science

textbooks of NCERT from classes 3rd to class 8th. The concept food has been

given a major place in the present curriculum designed by NCF, 2005. It is one

of the 7 given themes which form the core of both EVS and science syllabus in

primary and upper primary classes. The concept of food is introduced from

class III with topics on food of animals, various plant parts we eat, various

methods and utensils used for cooking, various methods of preserving food and

how food crops are grown in primary classes .The topics included under

nutrition at this level are types of teeth, digestion of food, anaemia and food,

glucose drip etc. The topics are dealt in the social context. At the upper primary

level the topics included under food are various components of food, balanced

diet, crop production, plant and animal sources of food etc and the topics under

nutrition are autotrophic and heterotrophic nutrition, animal nutrition, digestive

system in humans, digestion of carbohydrates, proteins and fats by digestive

juices, digestion process – ingestion-digestion, absorption, assimilation,

egestion, aerobic and anaerobic respiration, cellular respiration, food---

respiration – energy, products like alcohol, water, lactic acid or carbon dioxide,

digested food circulated through circulatory system.

Concept statements about Food and Nutrition included in elementary classes

as given in NCERT textbooks are as follows:

• Our food is derived from various plant parts and animal sources.

• We have different types of teeth to chew, bite and cut food.

• Digestion of food takes place in the different organs of the digestive system.

• Carbohydrates, proteins, fats, vitamins and minerals are important

components of our food.

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• Each component has an important role in providing energy, to build our

body and metabolism.

• Nutrition includes intake of food i.e. ingestion, digestion, absorption,

assimilation and egestion.

• Digested food is absorbed into the blood and circulated in the body through

circulatory system.

• Digested food gives energy through respiration.

• Respiration is of two types: aerobic and anaerobic.

• Organisms are autotrophs or heterotrophs depending on whether they make

their own food or not. Types of Heterotrophs, Insectivorous Plants

• Plants and Animals - Food Sources; Modes of Food Intake; Variety of Food

• Food gets spoiled if not stored properly.

The concept map developed by the researcher to show the hierarchy of

concepts included in the text books of NCERT elementary level is placed at

Figure 4.2. The concept map shows presentation of concepts in the upper

primary level compared to primary classes. There are many concepts to be

conceptualised within a short span of 3 years of upper primary level.

4.4.2. The Intended Concept Map: International Source

There are several concept maps available in text books and websites on the

concepts of food and human nutrition, but most maps are separate showing

hierarchical representation of the concepts of either food or nutrition along with

connecting ideas (Figure 4.3 & 4.4). The researcher has found the intended

concept maps from the international sources showing the concept of food and

nutrition starting from the concept of nutrients of food and extends up to

biochemical breakdown of food by enzymes and assimilation. The concepts

and sub concepts are scientifically stated. With standards movement in

countries like USA, UK, Australia, New Zealand, there is focus on scientific

literacy (Duit, 2007) of students. Science curricula are presenting hierarchical

progressions in a topic which follow one another as children learn about and

investigate in a broad span of 6-8 years (Ducshl et al, 2007).

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Source: http://www.slideshare.net/dhmcmillan/food-and-digestion-concept-map-presentation

Fig. 4.3: Concept Map on Food from Web Resource

Source: http://www.google.co.in/imgres?imgurl=http://shida810.files.wordpress.com/2010/10/digestion.jpg

Fig. 4.4: Concept Map on Digestion from Web Resource

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The progression maps from other sources shows the concept of energy and

matter integrated with food and nutrition which is scientifically stated but is left

to scaffolding by the teachers to relate to the context of the learners.

4.4.3. Derived Concept Map: Food and Nutrition

A concept map is developed merging the two- ‘food’ and ‘nutrition’ strands

together from other sources and balancing it with the NCERT map. The

researcher’s concept map has connecting ideas from food and its components

on the left side and connections between the digestive, respiratory and

circulatory system on the right side (Figure 4.5). It has fewer concepts

compared to the concept map developed from NCERT text books. The relevant

concepts have a focus on food and human digestion only. The ramifications of

the topic into animal or plant nutrition or agricultural practices are omitted.

In the Indian context, at the primary level, contextual knowledge about food

eaten in different parts of the country is given importance in the food strand.

Further, children are introduced to ways of cooking, eating in the family, food of

animals and human beings, how food is grown and reaches us, spoiling of

foods, which are topics in the social context of children. In the nutrition strand,

digestion of food in mouth is introduced.

At the upper primary level, the strand of food and nutrition has been dealt in

detail. The sources of food derived from plants and animals, components of

food viz: carbohydrates, fats, proteins, vitamins, minerals, fibres and their

sources, balanced diet, deficiencies, crop production and spoiling of food by

micro-organisms. The strand nutrition includes human digestion and respiration

without going into details of biochemical breakdown of food by different

enzymes or physiological processes within different organs.

Textbooks by NCERT stress more about contextual knowledge on food &

nutrition as idealized by its policy of constructivism.

Concept statements about Food and Nutrition included in the derived concept

map developed by the researcher for elementary classes are as follows:

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Fig. 4.5: Derived Concept Map – Food and Nutrition (Developed by the Researcher)

• Our food is derived from various plant parts and animal sources.

• Food can be classified in several ways : food from plants and animals, food

from different parts of our country, junk food and nutritious food ,food for

animals and humans

• We have different types of teeth to chew, bite and cut food.

• Carbohydrates, Proteins, Fats, Vitamins and minerals are important

components of our food.

DIGESTION

FOOD AND

NUTRIENTS

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• Each component has an important role in providing energy, to build our

body and metabolism. Some food items are rich in one or more nutrients.

• Balanced diet provides us energy, maintains good health and provides

material for growth.

• An unbalanced diet may lead to deficiency diseases or obesity.

• Water though is not food, is required in the body for digestion and keep the

body hydrated.

• Fibres must be included in the diet for their role in healthy and efficient

digestion and bowel movement.

• Nutrition includes intake of food i.e ingestion, digestion, absorption,

assimilation and egestion.

• Digestion of food is a bio-chemical as well as mechanical process which

takes place in the different organs of the digestive system.

• Several glands are involved in the digestion of food. Food gets digested by

several enzymes secreted by those glands.

• Digested food is absorbed into the blood and circulated in the body cells

through circulatory system.

• The absorbed substances are used to build complex substances such as

proteins required by different parts of body, this is called assimilation.

• Digested food gives energy through respiration inside cells. Respiratory

system is involved in providing oxygen and removing carbon dioxide from

the body.

4.5. Students’ Conceptions of Food and Nutrition: Primary Source

In the first section, scientific perspective has been explored via the path

treaded by scientific community for over two thousand years during which the

content area of food and nutrition evolved. This exercise helped the

researcher to know the strands within the content area of food and nutrition. It

is imperative to know the conceptual resources present with the students for

whom the big ideas are meant. Pedagogical perspective of food and nutrition

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concepts was built by reviewing the research literature about students’

understanding of related concepts. The existing intended curricula in the

Indian and international context were analysed to comprehend the coverage

and depth of the ideas about food and nutrition meant for elementary

students. From this understanding, a concept map on food and nutrition was

developed (Figure 4.5) on the basis of which questionnaires were developed.

The purpose of this part of the study is:

• to identify the conceptual ideas of students in food and nutrition from class

4th to 8th

• to explore whether there is progression from contextual knowledge to more

scientific understanding

• to explore the trajectory of students from phenomenal to conceptual

understanding and macroscopic to microscopic understanding.

Tool Development

The outlines of the food and nutrition concepts were divided into 2 strands such

as (i) food and nutrients and (ii) digestion-system and process. Several

questions were framed on each strand keeping in mind the concept behind it

and the learning process in terms of identifying examples, differences,

definitions, meaning or finding relation etc. For example: Is water food for plants

and animals?

a. Yes, because water is taken in by plants and animals

b. Yes, because water is necessary for plants and animals

c. No, because liquids are not food for plants and animals

d. No, because water does not provide energy for plants and animals.

Relevant research studies were referred to search for appropriate assessment

items that could reflect students’ thinking. Some questions were derived from

few of research studies. These questions in the form of open-ended were

administered as pilot study and the final questionnaire has taken into

consideration the choices given in the research studies as well as the students’

choices. The questions thus formulated were ratified through expert opinion

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and placed in a questionnaire. These questions were piloted in a school with

around 40 students in each class from class 4th to 8th. The responses on this

set of questions were analyzed. The discrepancies in language were removed.

Minor modifications were made on the basis of whether or not the content of

the modules was comprehended by the students.

The sample for collecting data from primary source constitutes approx 200

students across each class from Class 4th to Class 8th from 5 schools of Delhi,

2 of which were Kendriya Vidyalayas and 3 were Public Schools of Delhi. The

purpose of choosing the Kendriya Vidyalayas was that they represent the

government set up with students from diverse socio-economic and linguistic

backgrounds. The 3 Public Schools cater to a similar clientele and also have

similar infrastructural and instructional facilities and all five schools were

affiliated to the CBSE & hence have similar curricular exposure.

Tool

The questionnaire on Food and Nutrition has 2 to 3 questions each on the

concepts of different food materials, nutrients in food, role of food in our

nutrition, digestive system and digestion. While younger students were asked

more about food materials and role of food in our body and digestion at a gross

level, older students were asked about role of nutrients in the body and role of

digestive organs in the body. There are overall 10 to 13 questions in the

questionnaire on food and nutrition for the students of the 3 stages. Refer to

Appendix A, B and C.

Analysis Design

The responses of students were analysed to see a general picture of

elementary learners’ conceptions about food and nutrition and difference

amongst stages from mean, standard deviation, and applying one way ANOVA

with 3 groups (stage 1, 2 and 3) and chi-square test of significance. Difference

within the stage that is between classes 4th and 5th and between 6th and 7th

were also tested for significance by chi-square test for all questions and also

between stages for select questions which were asked across stages.

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Percentage of responses, difficulty value of questions (hence concepts) were

analysed to see learners’ progression of concept within the sub-concepts.

Wherever students of different stages were presented with the same question,

data was presented through graphs and difference was tested for significance

by chi-square test and difference if any is indicated in the following section

where individual concepts are dealt.

4.5.1. General Analysis of Students’ Conceptions about Food and Nutrition

The central tendency through mean and distribution of scores (standard

deviation) were analysed to find the general understanding of students in food

and nutrition. The central tendency of a distribution is an estimate of the centre

of a distribution of values. The mean or average is the most commonly used

method of describing central tendency. To compute the mean all the values

were added up and divided by the number of students.

The mean of the students’ performance in the questionnaire on food and

nutrition and standard deviation across stages is as follows:

Table 4.2: Mean and S.D. across Stages

Food & Nutrition Stage-1 (N=401)

Stage-2 (N=360)

Stage-3 (N=196)

Mean 44.79 47.84 53.19

Standard Deviation 11.49 19.95 14.96

An observation of the mean shows that students of stage 3 performed better on

the test on the food and nutrition concept compared to the rest of the classes.

Older students understood better, i.e. stage 3 performed better than stage 2

and stage 2 performed better than stage 1 (Table 4.2).

One-way ANOVA was used with the three groups of students, stage 1, stage 2

and stage 3 to investigate statistical differences among them. The statistical

results were interpreted only if the data met a basic assumption for the use of

ANOVA, i.e. the variances of three groups were similar (homogeneity of

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variance). The quantitative data results indicate there are statistically significant

differences among three groups on their performances in the food and nutrition,

F (2, 954) =18.55, p< 0.05.The stage 3 (N = 196, Mean = 53.19, S.D. = 14.97)

outperformed the stage 2 (N=360, Mean=47.84, S.D=19.96) and stage 1 (N =

401, Mean = 44.79, S.D = 11.49). There is no significant difference between the

stage 2 and stage 1 on their performance (Refer to Appendix D).

The data indicate that as students progress through the science curriculum

from primary to middle level, there is a progression in their knowledge about

food and nutrition.Stage1 had studied more about food than about nutrition,

stage 2 had both the concepts; stage 3 did not study much about both

concepts. Cognitive maturity of stage 3 appears to shift their understanding

about food and nutrition towards progression. A bigger sample with a full range

of questions on food and nutrition may help to make more definitive

conclusions.

Since the purpose of present research is to find the concepts which are

conceptualized by learners easily or with difficulty, a simple difficulty value was

computed. The concepts with 0 to 0.40 difficulty values (D.V.) were considered

difficult, concepts with 0.41 to 0.60 D.V. were considered as having average

difficulty, and concepts tested with 0.61 D.V. to less than 1 were considered

easy. The questions asked were not instruction/curriculum based; hence a

large value (of 0 to 0.4 or 0.61 to 1) was allocated to difficult or easy concepts

not to lose any valuable data (refer to Appendix G).

Table 4.3 presents the difficulty continuum of food and nutrition concepts

across the 3 stages. It is found that concepts found difficult in stage1 seemed to

be easy for stage 2 and so on. Students of all the 3 stages found concepts

related to food easy. Concepts related to food and related to students’

experience like seeds, meat, ghee were conceptualized by students of all 3

stages & were easy for all. Concepts related to transformation of food inside

digestive system and assimilation in the body was found difficult by all.

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Table 4.3: The Difficulty Continuum of Food and Nutrition Concepts across Stage 1, 2 & 3

D.V. Stage 1 Stage 2 Stage 3

Easy (0.61 to < 1) concepts

- Seeds as food

- Meat as food

-Role of food in the body

- Ghee has nutrients such as fats

- Energy is required to digest food.

- Glucose as food

- Role of food in the body

- Eggs as food items made up of cells

- Chemical breakdown by juices from glands

- Function of stomach

- Sequence of digestion

Average 0.60 –0.41

- Glucose as food

- Milk as a wholesome food

- Calcium is present in bones

- Digestion starts in mouth

- Function of stomach

- Pulses and eggs are body building foods

- Chemical breakdown of food by juices from glands

- Micronutrient requirement in body

- Digestion is complete in small intestines

- Meaning of digestion

Difficult 0.44-0.0

- Insects as food

- Flowers as food

- Pulses and eggs are body building foods

- Role of nutrients in body(only carbos)

- Identification of minerals

- Digestion is complete in small intestines

- Identification of nutrients in given diet

- Absorption of food from digestive system

- Identification of minerals

- Digestion is complete in small intestines

- Body structures grow from rearrangement of particles of food

From this study of students’ conception about food and nutrition from age 9 to

13, it was found that students of stage1 find many concepts (as many as 6

concepts) difficult. Five of these concepts are related to nutrients in food and

one is related to digestion. They found the conceptualisation of role of nutrients

in the body difficult to understand. They also could not conceptualise about the

process of digestion though they understood how digestion starts in mouth.

They found classifying food items which they are familiar with like meat and

seeds easy, but found identification of insects and flowers difficult.

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Similarly if the conceptualisations of students of stage 2 (11 and 12 years) are

considered, they found four concepts difficult. Their conceptualisation about

digestion, role of various organs or sequence is better than the students of 9 or

10years. They could not identify nutrients in food items which shows their lack

of content knowledge about nutrients and hence balanced diet also. Chemical

transformation process takes place with the help of glands is conceptualised by

many, but the absorption and assimilation is not understood by most students.

The students of 13 years of age have conceptualised most concepts related to

food and nutrition inquired of them. They did not find most concepts difficult

except one concept on the assimilation of food and growth. Conceptualisation

of it will require understanding of particulate nature of matter and conservation

of matter (Leeds National Curriculum Science Support Project, 1992).

The possibility of progression of elementary learners within sub-concepts is

analysed and interpreted comprehensively in the following section.

4.5.2. Comprehensive Analysis of Students’ Conceptions about Food and

Nutrition

The development of understanding about food and nutrition involves

understanding many aspects of it such as different food materials, nutrients in

food, role of food in our nutrition, digestive system and digestion. In this section,

it will be investigated if the concept sequence within food and nutrition is

supported by student responses to items addressing the above aspects.

An analysis was done to find percentage of responses of each concept asked.

Students’ responses were analysed to find whether they corresponded to

scientific conceptions or alternative conceptions.

Scientific Conception – The term ‘scientific conceptions’ refers to those ideas

about a particular concept or subject that are presently shared by the scientist

community. The use of the term ‘scientific conception’ instead of the ‘correct’

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conception is depictive of the dynamic nature of science and allows scope for

the possibility of revision of scientific knowledge which is how the disciplinary

knowledge develops.

Alternative Conception – The term ‘alternative conceptions’ in this study refers

to all ideas which differ significantly from the accepted scientific view (Gilbert,

1983). In the present study the term ‘alternative conceptions’ may include within

its purview:

- Pre-conceptions that have survived formal instruction.

- Hybrid conception resulting from the interplay between formal and pre

conceptions. These may not be entirely incorrect ideas but may incorporate

some correct ideas as well.

- Limited conceptions.

An analysis was done to find percentage of responses for each concept asked.

Chi-square test of significance for all questions on food and nutrition between

classes 4th and 5th reveals that all 15 questions except 2 questions showed no

significant differences. Those 2 questions have been indicated for the

difference in the following section. The chi-square test shows that classes 4th

and 5th are more homogeneous and it is logical to include them in one stage,

i.e. stage 1.

Chi-square test of significance for all questions on food and nutrition between

classes 6th and 7th reveals that all 11 questions except 3 questions showed no

significant differences. Those 3 questions have been indicated for the

difference in the following section. The chi-square test shows that classes 6th

and 7th are more homogeneous and it is logical to include them in one stage,

i.e. stage 2.

On the basis of their responses, students’ conception about food and nutrition

was summarised as follows.

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4.5.2.1. Students’ Conceptions about Food and Nutrients

There are 7 questions for students of stage1 (class 4th and 5th) and 5

questions for students of stage 2 (class 6th and 7th) on strand ‘Food’ in the

questionnaire and there are 3 questions in the questionnaire meant for students

of stage 3 (class 8th) on the same topic (Refer Appendix A, B and C). Since

younger students have more exposure about food they were asked more

questions on it. The questions were related to their understanding of what is

food and what is not, identification of nutrients, role of nutrients in the body. The

students’ conception about water as food, role of nutrients, identification of

minerals in food, has been traced from stage1 and 2 (classes 4th to 7th). The

understanding of glucose as food and role of food in the body has been traced

from stage 1 to stage3. The first half of the questionnaire was on food and its

nutrients and the concepts of elementary students on food were found to be

very similar to the findings mentioned in the research studies quoted below.

Hart K.H., Bishop J.A. and Truby H. (2002) employed a qualitative method and

114 children aged 7-11 years across age, gender and socio-economic status

(SES) were the sample. Across the groups, restrictive food rules were reported

and gender and SES difference were apparent in relation to parental control

over food and children’s nutritional knowledge. The limitation of the children’s

cognitive development was seen in their conceptualization of food groups, and

in the lack of understanding in their food-health or food – nutrient association.

Francis R. and Hill D. (1993) investigated the concepts held about food and

nutrition by students in grade 4, 8 student-teachers and parents of grade 4

students. They found that for many concepts relating to food selection, the

basic ideas were consistent among the groups despite the influence of formal

education. In particular, misconception about energy and its role in nutrition and

particular food groups was an important finding.

Sheila A. Turner (1997) conducted an action research project involving primary

teachers on in-service teacher education program in London. The research

aimed to investigate children’s knowledge and understanding about food and

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diet. Teachers interviewed children aged from 5 to 12 years. Pictures of food

were used to identify how children choose food to eat and how they classify

foods, and to explore their understanding of nutrients. The findings suggested

that even five year olds have some understanding of relationship between food

and heath. Children also held alternative ideas about food, especially about the

function of food and the importance of specific nutrients.

Tables 4.4 to 4.16 present elementary students’ conceptions about food.

Table 4.4: Food and Non-food

Concept

Stage 1

Class IV & V Age 9 to 10, N=401

Scientific Concept Alternative Concepts

Insects as food 8.2% 91.8% think insects are not food

Seeds as food 65%* 35% think seeds are not food

Meat as food 89% 11% think meat is not food

Flowers are food 12% think it is food 88% think this not food

* Significant difference detected: Chi-square statistic=9.36, df =1, p<0.05.

Students of stage 1 (ages 9 to 10) were asked to classify six types of food

items like meat, seeds, insects, flowers, glucose and water into two categories

of whether they are food or not. Their classification about water and glucose is

presented in tables 4.5 and 4.6.

Around 65% of stage 1 (58% of class 4th and 72% class 5th) conceptualised

seeds as food; rest of the students could not understand seed grains being our

mainstay in food. Around 89% understood meat being food. Most students had

difficulty understanding that insects and flowers can be food of either humans

or animals (Table 4.4). Though the topic is part of primary text books in Class

3rd, many did not think that people might be eating flowers or insects. They had

human centric view point, did not consider animal nutrition at all. This is similar

to the findings of Lee, Y.J. and Diong C H, (1999) that even secondary

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students’ (age 16-18 years) understandings of the biological concepts of food

were anthropocentric and not applied across living organisms in heterotrophs or

autotrophs as a whole. Simpson and Arnold (1985) surveyed children from

aged 11 to age 15, and suggested that many children associated ‘food’ only

with substance that they can identify as being edible. In younger children this

includes culturally appropriate human foods, whereas in older children it is

extended to examples from wider cultures and other organisms.

Table 4.5: Water as Non-food

Concept

Stage 1 Stage 2

Class IV & V

Age 9 to 10, N=401

Class VI & VII

Age 11 to 12, N=360

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Water as food Above 60% accept water as food Above 73% accept water as food.

In the classification task, 60% of stage1students thought water to be food. Above

70% students of stage2 consider water to be food because water is necessary

for plants and animals. Text books present water as a component of food while

some nutrition specialists consider that organic substances only can be food. Lee

Y.J. and Diong C.H. (1999) too have reported in their study that many students

confused the concept of nutrients and water, believing water to be food.

Research on Nutrition by Project 2061(American Association for Advancement of

Science, AAAS, 1993) report that lower elementary school children may believe

that food and water have equivalent nutritional consequences.

Table 4.6: Glucose as Food

Concept

Stage 1 Stage 3

Class IV & V

Age 9 to 10, N=401

Class VIII Age 13, N=196

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Glucose as food 56% Not food 44% 68% Not food 32%

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While 56% stage1 think that glucose is food in the classification task, 68% of

stage3 students think that glucose is food (Table 4.6). The context given for

stage3 students is glucose administered intravenously to a patient. For around

15% of older students, glucose is not food and 12% remain unsure whether

glucose is food or not. These 27% students may be considering anything taken

orally to be food and not intravenously.

Fig. 4.6: Glucose as Food

Table 4.7: Role of Nutrients in the Body

Concept

Stage 1 Stage 2

Class IV & V

Age 9 to 10, N=401

Class VI & VII

Age 11 to 12, N=360

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Pulses, eggs are ________ foods

Body building 28%

Energy giving 51% Others 21%

Body building 57.5%*

Energy giving 26% Others 16.5%

* Significant difference detected: Chi-square statistic = 11.54, df =4, p<0.05

Protein-rich food items like pulses etc. were identified as body-building food by

57.5% of stage2 (50% of class 6th and to 65% students of 7th), but 26% think

56 56

68

0

10

20

30

40

50

60

70

80

Class IV Class V Class VIII

Pe

ren

tag

e

Glucose as food

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that they are energy giving foods. Correct response increased in class 7th by

15% and incorrect response decreased. Influence of curriculum was seen in

class 7th, though topic is introduced in class 6th. Only 28% of stage1 identified

pulses etc as body-building food, but 51% of stage1students think that they are

energy giving foods. Lucas A. (1987) had found in his survey of 1033 adults

that they were familiar with the names of dietary components but not with their

functions: 37% thought that proteins provide most of energy needs of human

body and 19% thought vitamins do. He also found that proteins are more

frequently identified with food by 1045 students of ages 10-19: most of this

sample selected proteins as product of photosynthesis, presumably relating

proteins to food.

Table 4.8: Role of Food in the Body

Concept

Stage 1 Stage 3

Class IV & V Age 9 to 10,

N=401 Class VIII

Age 13, N=196

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Role of food in the body

88.3% 11% Why we eat food

54% to get energy

20% think we eat to allow the body to function

9.2% for tissue growth & repair

On the concept, role of food in the body, stage 1 students were logical in opting

for many roles of food for growth, energy and good health (Table 4.8). Sheila A.

Turner, (1997) investigated children’s (aged from 5 to 12 years) knowledge and

understanding about food and diet. Pictures of food were used to identify how

children choose food to eat and how they classify foods, and to explore their

understanding of nutrients. The findings suggest that even five year olds have

some understanding of relationship between food and health though they hold

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alternative ideas about food, especially about the function of food and the

importance of specific nutrients.

A slightly different question was asked to stage-3 students on why we eat food.

About 54% of the students think that we eat food to give energy; 20.4%

students think that food allows the body to function. Leach J., Driver R., Scott P.

and Wood R.C. (1992) studied progression in understanding of concepts of

food and energy as part of ecology concepts in students of 5 to 16 years. They

found that younger children of 5 to 7 years (Key stage1) do not attribute any

physiological function to food and think that food is a source of energy rather

than of matter for growth and that matter for growth may come from within the

body/seed. Slightly older children of 7 to 11 years (Key stage 2) think the same

about food and energy except that they develop little more knowledge about

food matter turning into body matter. Students of ages 11 to 14(Key stage 3)

have little knowledge of food matter being transformed to body matter and they

have the idea that plants get food from soil. Students of 14 to 16 years (Key

stage 4) have the idea that food is a scarce resource in ecosystems and that

plants get food from soil. They too have little knowledge about food matter

being transformed to body matter. They rarely distinguish food, matter and

energy.

Table 4.9: Role of Nutrients in the Body

Stage-1 Class IV and V Age 9-10 years, N=401

Concepts Scientific Concept Alternative Concepts

If we eat only rice for a month, what happens __________

Falls ill with deficiency 32% People will grow fat 36%

People will grow thin 32%

Students of stage-1 when asked to answer what happens if one eats only rice

for a month, almost equal number of students thought they would grow fat or

thin or would fall ill with deficiency (Table 4.9). Students do not attribute any

particular role to a group of food like carbohydrates, so they are equally divided

between all possibilities. Inagaki and Hatano (1987) report from their research

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on young children that almost all the children of 4-5 years recognized that

weight change is caused by food intake rather than intention or desire. Lee and

Diong (1999) asked similar question to 66 students of age (16-18 years)

Singapore qualitatively and found that 78% answered scientifically and 11%

each thought that eating carbohydrates would make them either fat or thin.

Older students seem to understand this concept scientifically.

Table 4.10: Identification of Minerals

Concept

Stage 1 Stage 2

Class IV & V

Age 9 to 10, N=401

Class VI & VII

Age 11 to 12, N=360

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Calcium, Iron are examples of __________

Minerals 28% Vitamins 57.4%

Carbohydrates 12.5% Minerals 41%

Vitamins 50% Carbohydrates 9%

Only 41% students of stage 2 have the concept that Calcium, iron etc. as

minerals. Students of stage 1 identify Calcium, iron as minerals with difficulty. A

small percentage thinks that they are carbohydrates, but majority of them think

that Calcium etc are vitamins. There seems slight increase identifying minerals

from stage 1 to stage 2 (Table 4.10). So the concept is not clear to most.

Students of class 6th are taught about minerals as components of food.

Table 4.11: Nutrients in Milk – Stage 1

Concept

Stage 1, N = 401

Class IV & V Age 9 to 10

Scientific Concept Alternative Concepts

Milk is wholesome food, because it has _______, _____, _____

Vitamins, minerals sugar & proteins 57.6%

Because milk has proteins 40%

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Students of stage 2 tick the component of food which they think are present in

milk (Table 4.11).

Table 4.12: Nutrients in Milk – Stage 2

Stage 2 Class VI & VII

Around 30% know that milk has fats 20% have the concept of carbohydrates in milk

Little more than 60% recognize ‘proteins’ and ‘minerals’ as nutrients and identify proteins and vitamins to be present in milk

32% have the concept of minerals present in milk

On being asked why milk was considered a wholesome food, stage-1 students

marked many nutrients against milk. They know that milk contains important

nutrients, but whether it has many nutrients, they are not aware. Students of

this stage do not understand that milk has fats. Around 30% students of stage 2

know that milk has fat. Less percentage of students selecting carbohydrates in

milk shows that most students of stage 2 do not understand that the milk has

carbohydrates in the form of lactose (Table 4.12).

Table 4.13: Nutrients in Protein Rich Food- i.e. Chana and Ghee

Concept

Stage 2, N=360

Class VI & VII Age 11 to 12

Scientific Concept Alternative Concepts

Nutrients present in chana are Proteins 44% -

Nutrients present in ghee are 90% Around 20% have the concept that ghee has all nutrients

Only 44% students of stage 2 understand that chana (black gram) has proteins.

More than 90% correctly identify fats with ghee. The response of students to

questions on identifying nutrients present in some common food items showed

that students were familiar with the names of dietary components but were not

familiar with the type of food items which have them. Research by Brinkman and

Turner (1991) suggests teaching did not change certain ideas of Dutch and

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English teenagers about fat in the diet. A small number of students (about 10%)

think that it is not necessary for your health to eat fat. Fat tends to be associated

with unhealthy food. Dixey R, Sahota P, Atwal S and Turner A (2001), presented

data from focus groups with 300 children (aged 9-11) in 10 schools in Leeds,

UK. Analysis of the frame scripts shows that children understood the

relationship between their diet and health, both present and future. Fat played a

predominant role, with a healthy diet being one that did not contain too much fat.

To the contrary, the common alternate conception about ghee in 20% of our

students was that fats have all nutrients, suggesting that it is healthy to eat ghee

according to them. Similar findings on misconceptions about several nutrients in

adults were concluded by Lucas (1987) also referred to after table 4.7.

Table 4.14: Element Present in Bones

Concept

Stage 1

Class IV & V Age 9 to 10, N=401

Scientific Concept Alternative Concepts

Element present in bones is ___________ Calcium* 61% Iron 30%

Proteins 9%

* Significant difference detected: Chi-square statistic=18.99, df =3, p<0.05

About 61% of stage 1 (53% of class 4th and 69% of class 5th) identify the

element present in bones as calcium (Table 4.14). The topic is not part of their

syllabus, but because of exposure to advertisements about various health

foods containing calcium through mass media, students know that calcium is

present in bones.

Table 4.15: Components in Balanced Diet

Concept

Stage 2

Class VI & VII Age 11 to 12, N=360

Scientific Concept Alternative Concepts

What is missing in the diet consisting Roti, vegetables &

potatoes Proteins 36%

Fibre 45% Carbohydrates 19%

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A question meant for students of stage 2 was on balanced diet. Students had to

identify what is missing in a combination of food items in Nina’s diet in which

food with proteins are not present (Table 4.15). Students do not know about

components of food, so around 36% only identified proteins. Around 45% think

fibres are missing from her food, while fibres are present in the given

combination in the form of roti and vegetables, so maximum students do not

identify fibre either. In the correct response, maximum contribution is of high

achievers, so it is not guess work by low achievers either. S.A. Turner (1997)

too found the lack of knowledge about fibres in primary children which she

reported was a cause of concern.

Table 4.16: Food made up of Cells

Concept

Stage 3

Class VIII Age 13, N=196

Scientific Concept Alternative Concepts

___________ is the food item made up of cells

Eggs 93% Oils 4%

Students of stage-3 had to identify food items made up of cells. About 93%

have the concept that eggs are made up of cells (Table 4.16).

Arnold (1983) and Simpson (1983) investigated on 249 14-15 year-old Biology

students in six British schools, who had all been taught about food and

digestion. Three quarters of the pupils accept that carbohydrates and proteins

are made of molecules but a large minority thought that they are also made of

cells.

Table 4.17: Quantity of Micro-nutrients

Concept

Stage 3

Class VIII Age 13, N=196

Scientific Concept Alternative Concepts

Vitamins and minerals are measured in ________ units

Milligrams 51% Grams 34%

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Half of stage 3 has the concept that micro nutrients are required in milligrams,

but 34% also think that they are required in grams. Only calcium may be

required in grams (Table 4.17).

The conceptions of elementary students on food were found to be very similar

to the findings mentioned in the research studies by K.H. Hart, J.A. Bishop, H.

Truby (2002), Francis R and Hill D (1993) and Sheila A. Turner (1997).

4.5.2.2. Students’ Conceptions about Digestion

There are 3 questions in the questionnaire meant for students of stage1, 4

questions in the questionnaire for students of stage2 and 7 questions meant

for students of stage3 on digestion. The questions were related to their

understanding of meaning of digestion, the process of digestion, role of

different organs and glands in the body. Students’ conception about role of

stomach in digestion has been traced from stage 1 to stage3. The students’

understanding about role of gastric juices in the process of breakdown of food

has been traced from stage 2 and 3. The conception of students’ about

completion of breakdown process of food in the body has been traced from

stage 1 to stage 3. Tables 4.18 to 4.26 present elementary students’

conceptions about digestion.

Children are supposed to have some knowledge about digestion from age four.

Reiss and Tunnicliffe (2001) in their study of drawings of organs and organ

systems of human body of students from 5 to 20 years also found that the most

well-known systems are digestive systems and the respiratory system. Susana

Gracia-Barros and others (2011) investigated 342 Spanish young children’s

(aged 4 to 7) evolution of knowledge about the digestive system and respiratory

system of the human beings and of other animals before they studied about

them at school by means of drawings made by children. They found that the

children recognized specific organs in their own bodies which they associated

with the intake of food and air and they usually extrapolated those organs to

other animals they were familiar with. Their ideas about the digestive system

were more adequate than the ones about the respiratory system. Their ideas

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improved as they become older, above all those concerning the digestive

system.

There are disagreements among researchers about the origin of the biological

domain in children. Carey (1985) claimed that the biological domain emerges

from the psychological domain. Keil (1992, 1994) stated that young children’s

initial biological theory is an independent and autonomous domain from

childhood. Hatano and Inagaki (1997) noted that biological knowledge is

constructed from inferences drawn from daily experience; hence it is application

of empirical knowledge to related contexts. If children possess biological

knowledge as an autonomous domain, then instruction in biology should be

effective. This effectiveness depends on the ability of the teacher to enhance

restructuring of their biological knowledge through enrichment and conceptual

change.

Table 4.18: Digestion of Food in Mouth

Concept

Stage 1

Class IV & V Age 9 to 10, N=401

Scientific Concept Alternative Concepts

Digestion of food starts in ________ Mouth 54% Stomach 30%

Students of stage1 were asked about where the digestion process starts.

Around 54% have the scientific concept that digestion starts in mouth. About

30%students have the concept that digestion of food begins at stomach. The

topic has been dealt with in class 5th, but there was no difference in the

understanding of students of class 4th and 5th. Yilmaz Cakici, (2005) has

reported in his study of 283 Turkish children's understanding of digestion in

Grades 4 and 5 (ages 10-11) through the use of an open-ended questionnaire

and follow-up interviews. In his study, even after teaching the unit on digestion,

only 20.4% children of class 4th and 34.9% of class 5th answered correctly that

digestion starts in mouth, more than 50% in class 4 and 47% in class 5th

answered that it started in stomach. Correct conceptions were more in the

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interviews. In the present study, higher number (54%) of students of the same

age has the scientific concept

Table 4.19: Chemical Breakdown of Food

Concept

Stage 2 STAGE3

Class VI & VII Age 11 to 12,

N=360 Class VIII

Age-13, N=196

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

__________ helps in chemical breakdown of food.

Juices from glands 52.4%*

Organs 17%, Water 11%, Hajmola 9%

Juices from glands 80%

Organs 8%, Water 4%,

Hajmola 6%

* Significant difference detected: Chi-square statistic=24.88, d f =4, p<0.05

Fig. 4.7: Gastric Juices in Digestion of Food

Students of stage 2 and 3 were asked about their conception on what helps in

the chemical breakdown of food in the digestive organs. About 52.4% of stage

2 (40% of class 6th and 65% students of Class 7th) understand that digestive

glands help in chemical break down of food in the digestive organs, 80% of

stage 3 students have the scientific concept (Table4.19). There is an increase

of 25% in recognition of digestive glands as helping in chemical breakdown of

food from class 6th to 7th and 40% increase in recognition by class 8th from

Class VI Class VII Class VIII

Digestion of Food 40 65 80

0

10

20

30

40

50

60

70

80

90

Pe

rce

nta

ge

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class 6th (Fig 4.7). Around 17% of students of 6th class select responses which

reflect misconception like hajmola and spices helping in chemical break down

of food. The topic on Digestion of food is dealt in the class 5th and 7th in detail.

Still majority of students of stage 1 and 2 did not have the scientific conception.

This is similar to Cakici (2005)’s finding about younger students of class 4th

and 5th; around 40% of class 4th and 56% of class 5th students had the

scientific idea that digestive juices in glands help in breakdown of food in

digestion while 38% of fourth graders and 27% of fifth graders also thought that

breakdown was because of water, acidic drinks, green plants or oils etc.

Table 4.20: Function of Stomach

Concept

Stage 1 Stage 3

Class IV & V Age 9 to 10, N=401 Class VIII Age 13, N=196

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Function of stomach is ________

Digesting 61% Storing food 23.5%

Filtering 9% Digesting 76%

Storing food 20% Filtering 2.6%

Fig. 4.8: Role of Stomach in the Body

51

71 76

30

172012.4

4.72.6

0

20

40

60

80

100

120

Class IV Class V Class VIII

Digesting Storing Filtering

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Students of stage 1 and 3 were put the question about the function of

stomach. Around 51% of the class 4th students understand that the function

of stomach is digesting, but 30% also think that storing is a function of the

stomach. An additional 12.4%thinks that stomachs filter food. There is an

increase of 20% in the correct response of class 5th, because the topic was

dealt in class 5th itself. Around 17% of class 5th students think that stomach

stores food, only 4.7% think that stomach filters food (Fig. 4.8). Their

responses are very similar to the conceptions of medieval physiologists

like Galen who wrote that stomach performed a filtering or storing role.

In Cakici (2005)’s study too, some children considered digestion to be a

filtering process that is performed by the stomach in order to separate the

useful and waste parts of food. These views 'melting of foods' and 'filtering of

foods' had not been mentioned in the literature previously than Cakici. On

being asked the same question, about 76% of class 8th understand that

function of stomach is digesting; still 20% have the misconception that it

stores food. This misconception seems to persist from stage1; however the

alternate concept of filtering role decreases considerably (Table 4.20).

Table 4.21: Digestion is Complete in Intestines

Concept

Stage 1 Stage 2 Stage 3

Class IV & V

Age 9 to 10 Class

VI & VII Age 11 to 12 Class VIII Age 13

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Scientific Concept

Alternative Concepts

Digestion (break down) of food finishes at ________

Small intestines 10.5%

Anus 49% Large intestine 24%

Small intestines 20.3%

Anus 40% Large intestine 24%

Small intestines 59%

Anus 26% Stomach 9.4% Large intestine 4.6%

On being asked where digestion (break down) of food finishes, around 49% of

students of stage 1 think that digestion (break down) of food finishes in anus.

Only 10.5% students of stage1 have the scientific conception that digestion of

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food finishes in small intestines. As in the case of stage 1 students, more than

75% of students of stage-2 do not understand where the digestion process

finishes. Only 20% of stage-2 students know that it finishes in small intestines.

About 24% think it is at large intestines. About 40% think digestion finishes in

anus. Around 60% of stage 3 students understand that digestion of food

finishes in small intestine and not at other organs. About 10% think that

digestion finishes at stomach. But still 26% of stage3 students think that

digestion finishes at anus (Table 4.21 and Fig. 4.9). Cakici (2005) had found a

lower percentage of correct conception in students of class 4th and 5th at 3.4%

and 7.2% respectively, while lower percentage of students at 18% of class 4th

and 13% of class 5th students had the conception that digestion finishes at

anus. This is probably because of number of distracters provided by him were

more than eight. Teixeira F.M. (2000), researched children’s conceptions of the

structure and function of the human digestive system based on data from an

investigation carried out with 45 children between the ages of four and ten. The

results indicate that the concept of transformation of food can constitute an

obstacle to comprehension of the scientific model of the functions of the

digestive system for children aged up to ten.

Fig. 4.9: Digestion gets completed in Small Intestines

0

10

20

30

40

50

60

70

Class IV Class V Class VI Class VII Class VIII

Digestion of food finishes

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Table 4.22: Absorption of Digested Substances

Concept

Stage 2

Class VI & VII Age 11 to 12 N=360

Scientific Concept Alternative Concepts

Digested substance go to ___________

Absorption takes place 32% Digestion is complete in stomach & pass to intestine 48% Remain in stomach 10%

About 48% of the students of stage2 think that complete digestion takes place in

stomach and then digested substances go to small intestines. Only 32% has the

scientific concept that digested substances are absorbed by blood from

intestines (Table 4.22). This notion mentioned above affects their understanding

about destination of substances obtained by digestion.

Table 4.23: Meaning of Digestion

Concept

Stage 3

Class VIII Age 13, N=196

Scientific Concept Alternative Concepts

Digestion of food is ________

Breaking down of food in stomach and small intestines and food entering into body 54.6%

Passage of food down organs 22% Role of stomach in digestion 11% Role of stomach in filtering 11%

Around 55% of stage 3 students correctly understand the process of digestion

of food; still 22% think it is simply movement or passage of food through mouth

to different organs before getting excreted through anus. Another 22% too

understand the process as filtering or breaking down of food. Cakici (2005)

reported that the most significant finding was around 30% of 4th and 20% of 5th

graders’ conception of the digestive process as 'melting of foods' rather than

'breaking foods down' and that there was an increase in the proportion in

children who considered breaking down of food in class 5th rather than melting,

but the difference was not significant.

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Table 4.24: Sequence of Process of Digestion

Concepts

Stage 3 Class VIII, N=196

Scientific Concept Alternative Concepts

The sequence of process of digestion is

Ingestion, breaking into simple substance,absorption, assimilation and egestion 65%

Breaking of simple substances 15% Perceive that absorption takes place first 14%

Similarly 65% of stage 3 identify the sequence of process of digestion correctly,

14% to 15% pick incorrect sequence thinking absorption or digestion takes

place earlier than ingestion or eating (Table 4.24).

Simpson (1984) found that at thirteen, children’s ideas of the sequences of

digestion are very confused, both in terms of the anatomical route and the

processes. Routes may include the trachea, heart, kidneys in some children’s

minds. The sequence of processes may start with breaking into soluble

particles, releasing energy, followed by swallowing.

Table 4.25: Energy Needed for Digestion

Concept

Stage 2

Class VI & VII Age 11 to 12, N=360

Scientific Concept Alternative Concepts

Is energy needed to digest the food we eat?

Yes 61% No 22%

Unsure 14%

Students of stage2 were asked if any energy is spent on digesting food.

Though only 50% of the students of class 6th understand that our digestive

system requires energy to digest the food we eat, 73% of class 7th understand

it correctly. This concept is the basis of understanding energy need for all the

body functions (Table 4.25).

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Table 4.26: Food and Growth

Concept

Stage 3

Class-VIII Age 13, N=196

Scientific Concept Alternative Concepts

If we do not eat for 2/3 days what will happens in our blood?

Fewer nutrients in blood 67%

No nutrients 18% No change in amount of nutrients 11%

Our body structures grow as __________

Particles from food (atoms) are rearranged to form particles of body structure 28%

Food accumulates inside body 38% Vitamins and minerals are added to the body unchanged 24%

While 67% of stage 3 students think that on fasting for 2-3 days there will be

fewer nutrients in the blood, 18% think that there will be no nutrients in the

blood. While 85% (67+18) seem to understand the relation between food and

nutrients, 11% do not understand it and 18% do not foresee any storage

mechanism for nutrients in the body.

To the second question shown in the table 4.26, only 28% think that particles

from food are rearranged in body, 38% think that food accumulates inside the

body and 24% think that vitamins and minerals are added to the body

unchanged. This finding is similar to the finding by Smith and Anderson, 1985

and Leach et al 1992 under CLIS project .They found that some students of all

ages think food is a requirement for growth, rather than a source of matter for

growth. They have little knowledge about food being transformed and made

part of a growing organism’s body. Francisco Nunez and Enrique Banet, (1997)

similarly described the conceptual patterns concerning human nutrition

encountered in a sample of 444 students aged between 11 and 17. They found

that only 69% of students of ages 16-17(who had studied biology) understood

the relation between cellular respiration and digestion and that digestion

converts complex nutrients into simple substances. The absence of an

association between digestion and circulation was a didactical obstacle (no

drawing with the passage of digested food into the blood in the school

textbooks) and an epistemological obstacle was the absence of understanding

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of the digestion of solid food and the permeability of the intestinal wall for the

passage of digested food into the blood was indicated by Carvalho (2004) in

her cross-sectional study of Portuguese primary school pupils.

4.5.3. Discussion

The following table gives the overall summary of the analysis from the primary

source.

Table 4.27: Scientific and Alternative Concepts across Stages

Stage 1 Scientific Concept Alternative Concepts

Food and Nutrients

Insects may be food Insects are not food

Seeds are food Seeds are not food

Flowers may be food Flowers are not food

Water is not food Water is food

Glucose is food Glucose is not food

Pulses and eggs are body building foods

Pulses and eggs are energy giving foods

Food has many roles growth, energy and good health

Food has few roles in the body

If we eat rice only we will fall ill with deficiency

If we eat rice only we may grow fat

Calcium and Irons are Minerals Calcium and Irons are Vitamins

Milk is wholesome food because it has minerals, vitamins, sugar and proteins

Milk is wholesome food because it has proteins

Element present in bones are Calcium Element present in bones are iron

Digestion

Digestion of food starts in Mouth Digestion of food starts in Stomach

Function of stomach is digestion Function of stomach is storing

Digestion break down of food finishes at small intestine

Digestion break down of food finishes at anus

Stage 2 Scientific Concept Alternative Concepts

Food and Nutrients

Nutrients present in Chana are proteins

Nutrients present in Ghee are fats Ghee has all nutrients

Water is not food Water is food

Pulses and eggs are body building foods

pluses and eggs are energy giving foods

Calcium and Irons are Minerals Calcium and Irons are Vitamins

proteins are missing diet consisting of Roti, Potatoes and vegetables

Fibers are missing

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Digestion

Juices from glands helps in chemical breakdown of food

Digestive organs, water, hajmola

helps in the chemical breakdown of the food

Digestion of food fines at the small intestines

Digestion of food finishes at anus

Digested substances are absorbed Digestion is complete in stomach and passed to intestines

Energy is needed to digest the food Energy is not required for the digestion

Function of Stomach is digesting the food

Function of stomach is storing

Stage 3 Scientific Concept Alternative Concepts

Food and Nutrients

Glucose is food Glucose is not food

Eggs are made up of cells Oils are made up of cells

Vitamins and Minerals are measured in Milligrams

Vitamins and Minerals are measured in Grams

Digestion

Juices from glands helps in chemical breakdown of food

Digestive organs, water, hajmola helps in the chemical breakdown of the food

Function of Stomach is digesting the food

Function of stomach is storing

Digestion of food finishes at the small intestines

Digestion of food finishes at anus

Digestion of food is breaking down of food in the stomach and small intestines and food entering the body

Digestion of food is the passage of food down the organs.

Sequence of the process of digestion is ingestion, breaking in to simple substances, absorption, assimilation and egestion

Breaking of simple substances

If are not consuming the food for three or four days there will be lesser nutrients in the blood

There will be no nutrients

Our body structures grow as particles from food are rearranged to form particles of body structure

Food accumulates inside the body.

From the primary data, one may generalise that students of higher class i e

older students understand concepts of food and nutrition better than younger

students; students’ understanding of concepts did improve in class 8th. Though

most of the food and nutrition concepts were part of science teaching at classes

6th and 7th, students of class 8th seemed to have understood them better than

classes 6th and 7th.

130

Understanding about food and nutrition concepts can be generalised only about

the items asked. Different patterns may emerge if other sub-concepts are

included in the items.The generalisations about findings in this study are

limited, since sample came from five schools that served diverse school

populations in terms of language, socio-economic status and achievement.

Tracing the trajectory of evolution of science concepts among elementary

students is challenging. Fundamental ideas tend to be abstract and

parsimonious, their appropriateness and usefulness cannot be appreciated by

students without the conceptual resources or epistemological commitment of

the practising scientific community. Owing to developmental and experiential

constraints of students, some of the food and nutrition concepts may be difficult

for students to understand. The constraints could be imposed by limitations

placed by curriculum.

Students of both classes within stage1 conceptualised about nutrients in food

and digestion in a similar way. Students of class 5th had their exposure to the

topic on digestion in curriculum, but it seemed to have marginal effect on them.

However, they understand the role of mouth and stomach better than class 4th

students. Teixeira (2000) found from his study of children’s conceptions about

digestion from age 4 to 10 that by the age of ten the function of the digestive

system is explained in terms of functions of organs. The age differences

suggest that children’s theory is built on the application of empirical knowledge.

The results indicated that the acquisition of the concept of digestion leads to a

conceptual revision and enrichment by the age ten.

Similarly if the conceptualisations of students of stage2 (ages 11 and 12) are

considered, their conceptualisation about digestion, role of various organs or

sequence is better than the students of stage1. They could not identify nutrients

in food items which shows their lack of content knowledge about nutrients and

hence balanced diet also. Most students do not identify what nutrients common

food items have and what is missing in a balanced diet .They identify fats and

carbohydrates easily. They know the importance of vitamins, minerals and

131

proteins, but cannot identify in food items. They understand the process of

digestion better than younger students, but most still have to conceptualise the

absorption of digested substances from intestines. The physical process of

transformation of food during digestion is understood. Chemical transformation

process takes place with the help of glands is conceptualised by many, but the

absorption and assimilation is not understood by most students.

The students of 13 years have conceptualised most concepts related to food

and nutrition inquired of them. They did not find most concepts difficult except

one concept on the relation between food and growth. Conceptualisation of it

will require understanding of particulate nature of matter and conservation of

matter. However, around 28% of students intuitively understand the relation

between food and growth shows that students at this age are probably

cognitively ready for abstract concepts like particulate nature of matter

.Osborne et al (1992) too have pointed out that an understanding of digestive

process requires a particulate view of matter and this is conceptually difficult for

children. Students may not understand digestion unless they are able to

comprehend that foods are transformed and broken down into blood. The

development of a particulate understanding involves matter such as food being

reducible to microscopic level at which it can be transported around the body.

Although the shape is changed during digestion, the total amount of matter

(food) does not change. The research on children’s understanding of the

particulate nature of matter by Brook et al (1984) showed that almost one fourth

of students aged 15 were incapable of understanding such idea. However, the

study by Skamp (1999) presents evidence that upper primary students can be

taught about the particulate nature of matter in a meaningful way.

According to Coleman G (2005), many nutrition concepts are abstract

concepts. However there are reasons to introduce nutrition concepts in

elementary school rather than wait until children are in the operational stage

where they begin to grasp abstract concepts. Educators might miss many

opportunities to promote understanding of nutrition if they wait until children are

able to comprehend abstract concepts because children are exposed to

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information on food and health messages from many venues including parents,

other people and the media throughout their lives. Providing food and nutrition

information that is concrete and relates to their life experiences can provide a

base for understanding abstract nutrition concepts late in life.

4.6. Conclusion

Due to vastness of the topic food and nutrition, the questionnaires developed to

probe into students understanding of related concepts could focus on limited

but important concepts in each topic. However, analysis of elementary

students’ understanding opened a window into the world of their understanding

of these concepts. Their responses show that though progression of many

important concepts occur across elementary classes, many important concepts

intended at a class are not grasped by them and they have certain alternate

conceptions. Many of the misconceptions are the same as reported in the

literature. The recommendations in terms of improved deliberate pedagogical

interventions to support conceptual understanding of students have been made

by researchers. However, the curriculum developers as well as textbook

authors need to take these into account while organising and sequencing

curriculum across elementary classes

The purpose of this part of the study has been to trace the evolution of

concepts of food and nutrition by elementary students. The analysis of

responses in this part may not provide an exhaustive understanding but

provides a cue for placement of concepts to attain progression.