Abuja — Minister of Education, Sam Egwu, on Monday said the desire of Nigeria to emerge as a global economic player by 2020 would require a science-based investment to drive the industrialisation process to fruition.

He said nations that have successfully scaled through the Third World status to gain recognition as industrialised did so through scientific-based knowledge and human capacity training in mathematics as well as sciences in general.

The minister made the remarks in Abuja at the inaugural conference of the Commission on Science and Technology for Sustainable Development in the South (COMSATS) organised in conjunction with the National Mathematical Centre (NMC).

According to him, "since investment in science is vital for developing nations, no socio-economic development can take place in any nation without sound education with science being the bedrock".

He said education must be made accessible and qualitative if Nigeria must build its education system to be competitive any time, anywhere in the world.

The meeting which is being hosted in Abuja, Nigeria since the inception of the COMSATS Consultative Committee in 1994 is usually used as an opportunity for developing nations to explore ways of addressing deficiencies in science education among member countries with a view to boosting its industrialisation status.

In another observation, Minister of Science and Technology, Alhassan Zaku, who was represented by Peter Onwualu, Director General of the Raw Materials Research and Development Council (RMRDC), stated that a country that neglects science education for its citizens does so at its own peril.

ABSTRACT

Physics is one of the ore science subjects being offered in Nigerian secondary schools and it forms the basis for the nation’s technological advancement. However, the quality of teacher training programmes in Physics leaves much to be desired. Consequently, the author re-examines the importance of physics education and makes some proposals on ways of improving the quality of teacher training, especially in physics in Nigerian universities

Introduction

Physics is a branch of science that deals with energy and matter and their interactions. It is sometimes referred to as the science of measurement and its knowledge has contributed greatly to the production of instruments and devices of tremendous benefits to the human race. In Nigeria, physics is being taught as one of the science subjects at the senior school level and its branches include mechanics, optics, atomic physics and physics of sub-atomic particles.

The importance of physics cannot be over-emphasised as it forms thebasis for technological advancement of any nation. Its study can lead to several scientific fields and professions such as engineering, manufacturing, mining and construction industries. Apart from this, the knowledge of physics plays a very significant role in the economic development of any nation. According to Amusa (1977), the promotion of physics has turned out to be the ‘sine qua non’ for rapid acquisition of technological know ow in most countries of the world. Smilarly, Abdullahi (1982) maintained that the contributions of physics toward making the world worth living and boosting the prestige of several nations are too numerous to mention.

In realization of its numerous advantages, physics has been introduced in Nigerian secondary schools at senior level in order to achieve the following objectives:

(i) to provide basic literacy in physics for functional living in the society;

(ii) to acquire basic concepts and principles of physics as a preparation for further studies;

(iii) to acquire essential scientific skills and attitudes as a preparation for the technological application of physics; and

(iv) to stimulate and enhance creativity (Federal Ministry of Education, 1985, p.5)

Problems of Physics Education

The aforementioned objectives look viable and relevant to Nigerian needs but their realisation remains vague as physics education is confronted by numerous constraints at senior secondary school level. Some of the identified problems are inadequate training of teachers at University level, poor attitude of students to physics, inadequate laboratory facilities, poor teahing methods, lack of instructional materials specifically designed to aid the teaching of physics, inadequate motivation and inadequate qualified staff (Daramola, 1982; Chukwumeka, 1985). Of these factors, the one of most interest to the author is inadequate training of physics teachers. This occupies an important position if one considers the importance of teachers in teaching and learning situations. According to Talisayan (1984), in developing countries, such as Nigeria, where science education receives little or not political support, the most important resource in the physics classroom is the physics teacher. He stressed further that an adequately trained and highly motivated physics teacher can rise above the constraining circumstances of paucity of material resources and government apathy. He therefore viewed that there is the need for teacher-education to produce self-motivating and effectively trained teachers wo will continually seek solutions to problems facing the classroom, those who will initiate changes to improve their teaching and those who will not wait for government or external funding to implement such changes.

Saha (1983) contended that the future of any nation lies in the hands of teachers. According to the researcher, the quality of the present day teachers determines to a large extent the quality of the future citizens of the schools. Also, Chukwuemeka (1985) pointed out that only effectively trained and professional science teachers can be expected to communicate the excitement of science and encourage curiority in students.

The teachers have a major role to play in the education of the students and the way and manner they play this role will definitely go a long way in determining whatever performance the students put up in their examinations. Consequently, for a physics teacher to effectively teach in a way that will lead to the development of desirable level of techno-scientific literacy he/she must be well groomed, be of sound knowledge in physics and he/she must obtain in the relevant professional teaching qualification(s) along with specialized knowledge of instruction. This becomes necessary in view of the findings that teachers’ professional qualifications influence students’ academicperformance (Willson & Garibaldi, 1976; Oguntimehin, 1987).

Proposal for Improving Teacher Training in Nigerian Universities

In view of the foregoing,the following proposals are considered relevant and appropriate for the improvement of training programmes for prospective physics teachers in Nigerian secondary schools.

Prospective physics teachers should be well grounded in the senior secondary physics content. They should also be exposed to the required mode of teaching these contents as well as the evaluation techniques in the three domains of educational objectives, which are cognitive, affective and psychomotor. Prospective teachers should learn different methods of teaching as well as practical ways of imparting physics education to students. They should be made to understand that physics cannot be taught effectively without practicum/practicals. Also, a situation in which what is learnt in the university is hardly reflective of the future encounter of the student should be discouraged in the universities. Earlier, Williamson (1969) revealed the need for greater breadth of preparation in the basic sciences for all prospective science teachers. If this done they would be exposed to different aspects of physics and consequently they would be able to impart the knowledge with little or no difficulty.

Most Nigerian universities run the course unit system which has a built-in flexibility and thus allows for freedom in choice of courses. However, this system does not seem to effectively prepare the prospective teachers who are supposed to teach all contents in senior secondary school curriculum. With this in view, the faculties of education in these universities need to make adequate arrangements to ensure that this gap is bridged through seminars, symposia, group discussion, extra-lectures, etc.

The need for constant follow-up courses for physics teachers cannot be over-stressed. Adequate provision in terms of financial and moral support should be provided to ensure that

physics teachers attend organizational conferences, seminars, workshops and in-service training in order to update their knowledge and keep pace with new development in the field of science.

Bajah (1975) observed that for any curriculum development with an ambition of positively changing the society to be successful, a number of factors are agents of change. Such factors include the universities, the parents, the teachers and the governments. Particularly, the universities should encourage lecturers to participate in science curriculum development. For instance, university science departments can organize a science curriculum development programme which could be accommodated within a university department. Also, university scholars in the sciences, lecturers in education and secondary school teachers could sponsor and conduct science curriculum development projects. The university scholars in the various science departments can provide the academic leadership, those in education an give guidance in the methodology to be adopted while senior secondary school teachers can form the link between the project and the students who are the consumers. It is when this is done that it can be realized that physics education programmes needs not include some specialist topics for the bachelor of science in physics. For instance, in physics, this writer agrees with Ivowi (1987) that there is no need for courses in Special Theory of Relativity, Low temperature physics, Geomagnetism, Plasma Physics, Radiation Physics, whereas solid state physics, modern physics, elementary instrumentation are considered relevant.

The writer also believes tat the teaching of physics courses that are irrelevant to the senior secondary school curriculum to prospective physics teachers may be one of the factors responsible for the easy drift (high turnover) of supposedly university graduate physics teachers to other sectors of the national economy thereby rendering teaching as a mere stepping-stone job. If a training in medicine offers opportunities for employment in medical fields only, a training in physics education should equally offer opportunities for employment in the teaching field alone. In other words, there should be an obvious disadvantage in going elsewhere to work after training in physics education.

The training programme of a prospective physics teacher should be expanded to allow for more sufficient exposure to relevant subject matter content so that the products of such training would have more sense of belonging to physics as well as relate their knowledge to the senior secondary school physics curriculum.

Finally, all institutions that train secondary school physics teachers, particularly Faculties of Education should co-operate to produce common curriculum guidelines for the physics components of the teacher education programme in order to ensure a uniform preparation for teachers of the same school physics curriculum.

Reference

[1]A CRITICAL APPRAISAL OF THE ROLE OF LABORATORY PRACTICAL WORK IN SCIENCE TEACHING IN NIGERIA

BY

ISAAC OLAKANMI ABIMBOLA

Abstract

The purpose of this paper is to sensitize science teachers and educators on the need to rethink the traditional role usually accorded laboratory practical work in science teaching. The historical evolution of the use of laboratory work in science teaching it-as traced to the early scientists. Then, the paper examined how the laboratory method first found favour with some science educators and how others later experienced disillusionment. Some initial suggestions were made that could replace or minimize the use of the laboratory method of teaching science.

Introduction

The use of the laboratory method of teaching science has become a dogma among science educators and teachers. On the one hand, they extolled the importance of the use of the laboratory method in science teaching while on the other hand, they only pay "lip service" to its use in practice. Science teachers do not usually find it convenient to make laboratory work the centre of their instruction. They usually complain of lack of materials and equipment to carry out practical work. At the same time, it is possible that some of these materials and equipment may be locked up in the school laboratory store without teachers being aware of their existence. The conditions under which many teachers function do not engender any enthusiasm to use the laboratory method of teaching science even where they know that these materials and equipment are available. Class size in urban schools is getting larger and this does not usually encourage teachers to use the laboratory method to teach science. In some states of the country, teachers go for months without salary owing to shortage of funds. Science teachers who fall in this category cannot reasonably be expected to give off their best to their students.

Higher institutions in Nigeria charged with the responsibility of training science teachers at all levels, are increasingly turning out teachers without requisite laboratory experience. A common reason usually given is shortage of laboratory facilities. Such trained science teachers usually lack the necessary confidence to conduct practical classes with their students. It is only

accreditation exercises that are improving this situation in Colleges of Education and Universities at present.

Such governments see, to have given up on their capacity to equip all school laboratories. They have therefore resorted to designating selected schools as "science schools" that they equipped with their meager resources. They usually used the traditional help received from the Federal Government in equipping school laboratories for these science schools. The condition of the national economy continues to deteriorate without any sign of improvement in sight. Is it not time to get realistic with our science teaching? I think it is high time we started.

The purpose of this paper is to sensitize science teachers on the need to look for alternatives to the traditional laboratory method of teaching science. First, I traced the historical evolution of the use of laboratory work in science to the early scientists' use of the experimental method. Second, I searched for answers to the question of why science educators think that the laboratory method should take a centre stage in science teaching. Third, I then provided evidences to illustrate, what I consider, a quiet disillusionment among some science educators concerning the role of laboratory work in science teaching. Fourth, I affirmed that the disillusionment is real. Then, I made some suggestions that could free science teachers and examination bodies from the dogma of laboratory work.

Origins of Experimental Science

The use of laboratory method in science teaching originated from the ideas of early scientists. The l7th Century is very significant in this respect. Mendelson (1982) has characterized the Century as the century of "The Scientific Revolution." This characterization is so because, according to Westfall (1971), "it was in the 17th Century that the experimental method... became a widely employed tool of scientific investigation" (p.115). The general feeling of disillusionment among scientists with earlier methods precipitated this trend. (Butterfield, 1957; Westfall, 1971). The feeling of disillusionment had to do with results of scientific investigations that did not match the efforts put into them. The scientists of the time blamed the method of conducting science, for the low output.

Taylor (1963) claimed that "the idea of experimental science began to have influence about 1590" (p.90) when scientists started basing their work on deliberately contrived experiments. According to him. "Galileo Galilei (1564-1643) was the first to employ the modern scientific method in the fullness" (p.91) in physics and astronomy. Before then, Westfall (1971) stated that Galen's writing on physiology contained examples of experimental investigation. Westfall also claimed that Robert Grosseteste of the medieval school. and the logicians based at the University of Padua, Italy, in the l6th Century, also discussed the precursors of hypothetico-deductive method.

However, it was in the 17th Century that scientists paid the greatest attention to the scientific method that led to a revolution in science. The sheer number of persons that paid attention to method then indicated the need for an acceptable method of conducting science. Francis Bacon (1561-1626) was perhaps the first in the 17th Century to formulate a series of steps to account for the scientific method in his hook Novum organum (The New Instruments, 1620), (Taylor, 1963). The book was a reaction to Aristotle's treatise in logic referred to as Organum. Bacon based his method on the inductive method of objective observation and experimentation without any preconceptions. Rene Descartes' (1569-1650) Discourse on Method based on mathematical reasoning and deduction closely followed Bacon's book. Westfall (1971) has credited Robert Boyle with perhaps the best statement of the experimental method that focused on "the activity of investigation that distinguishes the experimental method of modern science from logic" (p. 115). Pascal, Gassendi, and Newton also wrote on scientific method (Westfall, 1971). The emphasis on method during this period paid off with the several discoveries and inventions in the 17th Century and beyond, thereby giving the impression, albeit unintentionally, that science is synonymous with its method.

Importance of Science Practical Work

In Shulman and Tamir's (1973) review of research on science teaching, they identified three rationales generally advanced by those that supported the use of the laboratory in science teaching. The rationales included: (1) The subject matter of science is highly complex and abstract, (2) Students need to participate in enquiry to appreciate the spirit and methods of science, and (3) Practical work is intrinsically interesting to students. Shulman and Tamir also compiled a list of objectives of using laboratory work in science teaching. The list included the teaching and learning of skills, concepts, attitudes, cognitive abilities, and understanding the nature of science. Also, there is hardly any science method's book that does not usually list the objectives of science laboratory work (see, Abdullahi, 1982; Collette & Chiappetta, 1984). All

science curricula in Nigeria list practical activities that should go with each curriculum item listed. The current West African Examinations Council (WAEC) syllabus (WAEC, 1988) in use in 1996, recommended that the teaching of all science subjects listed in the syllabus should be practical based, perhaps, to demonstrate the importance it attached to practical work in science. Thus, several decades of emphasizing the assumed importance of laboratory work in science teaching have elevated the importance to the level of a dogma. Thomas (1972) and White and Tisher (1986) are of this opinion. This position is, perhaps, why Yager (1981) thought that science educators should treat laboratory work as the "'meal'-the main course" (p. 201) rather than an "extra" or "the desert after a meal" (p.201). Also, Bajah (1984) said, "All science teachers and students know that practical work is the 'gem' of science teaching" (p.44).

This dogma about the importance of laboratory work originated from the views of a few American educationists in the early sixties that extolled the importance of laboratory work in science teaching. Notable among these personalities are Bruner (1961), Gagne’ (1963), and Schwab (1960), They all extolled the virtues of teaching science as a process of inquiry or discovery. Before them, Dewey (1938) advocated learning by doing through his "project method" that he considered as a method of organizing the school curriculum on a scientific basis. Another American, Charles Pierce (Peirce, 1877, 1958) who advocated the use of the method of science as a mode of inquiry to satisfy our doubts, in turn, influenced him. The ultimate goal of these advocates of practical work was to train students in the ways of practising scientists so that students could become good scientists in the future. The surprise by which the former Soviet Union took the Americans, and, perhaps, the world, in launching the Sputnik into space in 1957, motivated their positions. Emphasis in science teaching at this time shifted from the products of science, what science to teach and learn, to the processes of science, i.e., how we teach and learn science (Bates, 1978). According to Shulman and Tamir (1973), this shift in emphasis lacked empirical evidence because the influence of the educationists mentioned above formed the basis of the shift. As a result of this influence, and the need to match the Soviet feat, the Americans commissioned and executed several curriculum development projects. Such curriculum development projects included the Biological Science Curriculum Study, started in 1959-, Chemical Bond Approach, started in 1958, Physical Sciences Study Committee, started 1956, and Science: A Process Approach, started in 1967, etc. They were all laboratory based. These curriculum development activities, with emphasis on laboratory work, spread to Nigeria, and elsewhere in the world.

Doubts About the Importance of Laboratory Work

Research into the role of laboratory work in science teaching has a long history. Blosser (1981) put the beginning date at the 1930's. These research efforts into the role of laboratory work in science teaching reached, their peak in the 1960's and 1970's during the curriculum development years. Abimbola (1981), Bates (1978). Blosser (1981, 1983), and Shulman and Tamir (1973) carried out reviews of research in this area. All of them concluded that science education researchers failed to provide conclusive evidence to support the view that using the laboratory method of teaching science is superior to other methods, at least, as measured by paper and pencil achievement tests. This conclusion is perhaps what prompted Leonard (1981) to exclaim that "Laboratory instruction is on trial" (p.445)- Also, the 1980-81 Board of Directors of the National Science Teachers Association (NSTA) in the U-S- recognized that there were widespread doubts about the importance of the laboratory in the seventies (Klein. Yager. & McCurdy, 1982), The Board thereafter put out a position statement in support of laboratory method of teaching science as follows:

The National Science Teachers Association endorses the necessity of laboratory experiences for teaching and learning in science. Adequate support for materials, equipment, and teacher time is available for schools to maintain quality science instruction. Such a quality program is critical in today's age of science and technology (Klein, Yager, & McCurdy, 1982, p.20. (emphasis in original)

Also, the Board commissioned various persons to write position statements to support the use of laboratory work at different levels of education and all the position statements appeared in one issue of The Science Teacher 49(2), 20-23. For instance. Tafel (1982) wrote for the Middle/junior School; Perez (1982) wrote for the high school; Bybee (1982) wrote for the "Basics" movement; Lunetta (1982) wrote from the curriculum perspective; Hurd (1982) wrote from the teaching perspective and Bates (1982) wrote from the research perspective.

The purpose of this section is to briefly provide examples of conclusions from the reviews mentioned above, part of which generated the reactions of the Board of Directors of the NSTA. For instance, in Abimbola's (1981) review of conceptions of discovery in science held by educators and philosophers of science, he concluded that the conceptions of discovery in science held by major schools of philosophy of science then, did not influence the "teaching by discovery" and "discovery learning" slogans. According to him, "the studies reviewed provided little elucidation about the efficacy of the discovery method of teaching and learning (p. 103). The discovery method of teaching and learning has as its main focus, the use of laboratory work in science teaching and learning.

Bates (1978), too, in a review of the role of the laboratory in secondary school science programs, concluded that despite seventy five years of studies in this area, the consistent conclusion is that "laboratory experiences neither help nor hinder student achievement - at least as measured by standard paper and pencil tests of subject matter" (p.68). Specifically, he found, among other things, that "lecture, demonstration, and laboratory teaching methods appear equally effective in transmitting science content" (p.74). Nonetheless, he found laboratory experiences to be "superior for providing students' skills in working with equipment" (p.74) and in maintaining students' interest in science. These are important objectives to achieve in science teaching and learning. However, how many of the skills acquired from laboratory work do students use in real life situations? Put differently, how does the lack of possession of these skills adversely affect the functioning of individuals in their daily life activities?

Shulman and Tamir (1973) upheld some of Yager, Englen, & Snider's (1969) conclusions about the need to question the central role of the laboratory in science teaching. They thought that science teachers could obtain desirable learning outcomes with limited laboratory experiences. Also, they concluded that, a verbal, non-laboratory approach might be best for some teachers and students. Some students may find laboratory activity a sheer waste of their time. They finally emphasized the need to structure some new courses that would deemphasize laboratory work without de-emphasizing the nature of science. We can achieve this restructuring of courses by giving equitable attention to the teaching of science concepts and principles, science process skills, and scientific attitudes without over emphasizing one over the others that was the case in the science programmes of the sixties and seventies. All this goes to show that the disillusionment is real.

In any case, studies in Nigeria and abroad have shown, too, that this disillusionment is real. For instance, studies have shown that science teachers themselves did not attach much importance to laboratory work as they usually found the slightest excuse to avoid them. However, if they attach importance to it there is no research evidence to support this importance (Abimbola, 1988; Bajah, 1984; Daramola, 1982, 1985, & 1986; Ndu, 1980: & Weiss, (1978). Important evidence, at least in Nigeria, that many science teachers are either not doing practical work at all or not doing enough practical work to give their students the confidence that they would pass their Senior School Certificate Examinations in science, is the extra-mural laboratory class being established in urban centres in Nigeria. Students that attend these classes must be missing something in their school laboratory work that they think they can find in the extra-mural classes. Also, the importance attached to laboratory activities did not match government provision of laboratory materials and equipment because they arc expensive to buy. There is therefore the need to explore alternatives to laboratory activities that would still preserve the nature of science.

Alternatives to Laboratory Work

Continuing to accord a central role to laboratory work in science teaching does not seem reasonable and feasible any more in the developing countries. I therefore intend to explore some alternatives to laboratory work for science teaching. Teachers that cannot do away with laboratory work can record on video tape well-planned demonstration experiments that they can later show to their students at appropriate times, Modern day secondary school students are likely to enjoy watching a video recording than carrying out laboratory work. This practice would save teachers and administrators some money and effort because it requires a one-time investment of money without further expenses on many consumable items.

Most traditional laboratory activities are gradually being banned in the developed countries either because of their health hazards or because of special interest groups. For example, animal dissection that used to be the core of biological experiments is gradually being phased out because of the influence of animal right activists, despite the spirited defence of animal use in the guidelines issued by the National Association of Biology Teachers (1980). The introductory statement of the guidelines goes thus: "Living things are the subject of biology and their direct study is an appropriate and necessary pan of biology teaching" (p.426). Computer simulations of dissection experiments are gradually becoming popular with schools. Interactive computer activities are gradually replacing laboratory experiments, thanks to the evolution of multimedia computer programs. Computer programs are also available for problem-solving exercises in the major sciences. The acquisition of computers by schools requires a one-time investment of money. The computers are also useful for other purposes apart from being used as an alternative to actual practical work. Computer simulations can only approximate the real feeling of working with live animals. However, for the knowledge gained by students from such an activity, the difference between the two activities is not likely to be significant.

The West African Examinations Council has already tried the "alternative to practical" form of examination with the Ordinary Level G.C.E., without many complaints. This form of examination requires candidates to answer questions on laboratory practical work off hand without having to do any laboratory work involving concrete specimens. This form of examination has not only saved the Council much money on the administration of laboratory practical examinations, it has also saved it time and effort usually expended on such examinations. Since most science teachers teach most practical lessons by the lecture method, they can go an additional step by examining their students using an "alternative to practical" method. My proposal is that if students listened and understood the teacher's lesson, they should be able to pass such examinations very well. The West African Examinations Council could

therefore extend its "alternative to practical" examination method to all its otherwise laboratory practical-based examinations.

Bloom (1956) has said that most of the subject matter content of most disciplines is informational. That is, the content involves the teaching and learning of basic concepts, laws and theories related to that discipline. The objective stated for any unit of instruction has been found to be generally in the ratio of the cognitive domain, 50%; the psychomotor domain, 25% and the affective domain 25%. If this proportion is so, and if students are able to master the cognitive component of their lessons, it should have transfer value on the affective and psychomotor domains. Abimbola & Danmole (1995) have recommended the use of content analysis method by concept maps to help students to understand the conceptual knowledge in science. Abimbola (1996) has also recommended the use of concept maps in constructing some of the items in nationally conducted examinations. Since teachers use some laboratory activities in science to elucidate what they had taught in science classes, if their students can achieve proper understanding of concepts and principles by using concept maps or other means, will the same goal of elucidation not have been achieved in a cheaper and perhaps, more effective way?

Conclusion

I have attempted in this paper to take a critical look at the traditional importance usually associated with the use of laboratory %work in science teaching and to question whether the status quo should continue. First, I traced the origin of laboratory work to the 16th Century and how it blossomed in the 17th Century thereby causing a scientific revolution. Second. I provided information on why educators, and science educators, in particular, usually think that laboratory work is crucial in the teaching and learning of science. Third, I provided evidences that I thought caused some science educators to doubt whether the usual importance ascribed to laboratory work in science teaching is not misplaced. The assertions of importance do not carry corresponding evidential support- In fact, results of some of the studies seemed to suggest that the use of laboratory work in science teaching did not make much difference in students' learning outcomes. Finally, I made some preliminary suggestions about what science teachers could use in place of laboratory work that would still preserve the nature of science and improve students' achievement in science.

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