effective lab teaching

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Effective Laboratory Teaching in the Biological SciencesGraduate Student Orientation

Fall 2010

Maggie Haag, Department of Biological Sciences

(BS CW312G; [email protected])

Outline

General Introduction/BackgroundGoals of Laboratory Work

Characteristics of an Effective TA (Uno, 1999)

Effective Laboratory Teaching:

Knowledge Session Plans organizing to teach Questioning Techniques delivery of the lab curriculum Cook Book vs Guided Inquiry vs Investigative Labs developing

effective labsSkills

Flow Charts organizing the skills and work plan effectively Facilitating Rather Than Directing guided inquiry

Effective CommunicationAbility to Interact in Positive MannerAbility to Evaluate Fairly and Consistently

Full handout available at the FGSR website

Notes:
mailto:[email protected]:[email protected]


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A. Goals for L aboratory Work

1. Learning scientific information and concepts;Participating in the construction of scientific knowledge, understanding the interplay of theory andmethodology;

2.Understanding the processes of scientific inquiry and appreciating and emulating the role of scientistsin inquiry:

Observing and measuring Seeing a problem and seeking ways to solve it Interpreting data and formulating generalizations Building, testing, and revising a theoretical model;

3. Developing imagination and creativity;4. Learning manipulative and technical skills and the use of equipment;5. Developing relevant professional values, attitudes and interests;6. Developing an orientation to the social, historical and philosophical aspects of science;7. Appreciating the application of knowledge and methods;8. Developing literature skills9. Learning how to communicate (verbal and written);

10. Learning to work cooperatively;11. Developing scientific attitudes and positive attitudes to science and stimulating interest, enjoyment andexcitement in science (Ramsden, 1992; Boud, Dunn and Hegarty-Hazel, 1989)

B.Characteristics of an effective TA? (adapted from Uno, 1999)

1. Displays a working knowledge of the material and lab techniques.2. Clearly explains how to use the lab equipment.3. Explains possible lab hazards, and insists on safe practices.4. Provides clear, appropriate instructions before and during the lab.5. Is attentive to the needs of all the students.6. Answers student questions and offers encouragement and useful advice.7. Gives fair and consistent evaluation on all aspects of student work.8. Encourages students to become self-learners and to engage in the discipline.

C. Effective laboratory teaching (preparation, preparation, preparation)

1. KnowledgeBeing knowledgeable about a discipline you are teaching is expected, however, being all knowingis not a prerequisite for effective teaching.But how can I be confident of my preparation and knowledge?

a. Common Preparation Strategies: review your notes from a similar course attend lectures if website, visit and review course material weekly prelab meetings with coordinator access to course textbook and teaching aids know where to access material organize material in a logical manner (session plan)

b. Other Strategies:

do preparation with a group or mentor present weekly prelab material to peers for critique and review

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understand the context of the theory in relation to the lab exercise that is being carried out;relate to course objectives and lab objectives

know the appropriate level of detail that students should understand (do they really need allthe details?); show how to condense or categorize to reduce volume/effort; suggest groupwork; get students to set up study groups (on-line or face to face).

use an example that the students can relate to before introducing a difficult concept ordifficult and/or new vocabulary

think of different ways of presenting material (questioning skills; using questioningtechniques (DVD) in prelab talks; changing cook book labs to guided inquiry or trulyinvestigative)

think of ways to test a students knowledge before they leave the lab:quizgame with a group of studentsan extension of lab (small discussion, PBL, investigative exercise)computer based self-testconcept mapping

2. Skills

Be 100% sure that you know the necessary skills and safety precautions to carry out the lab.Approach review or learning of skills from a students perspective. Students are not veryforgiving in this area.

a. Common strategies:

must have opportunity to use equipment ahead of time must know lay-out of lab, where to find materials, where to find assistance during lab must be able to understand and practice all aspects of laboratory safety must be able to relate importance of skill(s) to broader objectives of the course (discipline) must know how to do calculations and make sure you understand them; work through more

than one example; chose a relevant example

b. Other Strategies:

understand why the mastery of such skills/techniques are important to the lab and the biggerpicture of the course (life); use examples from every day life wherever possible

prepare a flow chart of necessary steps of an exercise so you are confident of the exercise;suggest that students do likewise

think/anticipate through the exercise (think like a student) and look for possible areas that willcause students problems; know potential hazards, safety precautions and disposal of potentialbiohazard materials

work through an exercise with a group of TAs to ensure proficiency know when it is important to demonstrate a particular skill/technique and when it is better to

have students learn by trial and error (including coming prepared vs coming unprepared);learn to be a facilitator not a commander

think of ways to test students proficiency of a skill before they leave the lab; even try tocombine a number of skills if feasible (see examples under Knowledge)

3. Communication (* covered in other workshops)

Students need to be able to understand your instructions and the information that you providethem with in the lab or when giving feedback on assignments. Both oral and writtencommunication skills must be clear, concise and given at a level appropriate to the students levelof understanding.

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a.Common strategies:

practice giving your prelab talk to peers or members of your lab group speak at an appropriate volume and with an appropriate tone; vary your speech be cognizant of the length of time to give either instruction and/or background information;

do not use the lab time to give a mini lecture

face your students when giving information if English is not your first language, use the board or overhead projector to clarify important

words, procedures, etc. prepare clear and concise acetates to illustrate important information or procedures

(remember the 7 X 7 rule) ask students if you are making yourself clear ask for feedback on your prelab talks, general aspects of your teaching during lab and in a

more formal evaluation at the end of the course; dont be offended by honest feedback

4. Ability to interact with students in a positive manner

To interact well with students instructors one must be credible. Fuller (1969) described fivedimensions of credibility: competence, trustworthiness, dynamism, composure and sociability.

Competence (knowledge and skills) Trustworthiness

-respectable, decent, honest and ethical-promote by being consistent, provide rationale for assessment, explain yourexpectations, carry out commitments or promises (lead by example)-always respect a students integrity

Dynamism-being outgoing and having energetic personality-can improve above by being interested in your topic and using interesting examples;need not be a performer

Composure-shows you are confident and in control

Sociability-friendly, pleasant manner and attitude-cultivate a positive attitude, smile, listen carefully-use their names and get to know them-let them know something about yourself, what it was like for you to be anundergraduate, research, goals, dreams, fears, etc.-be friendly but do not fraternize with them excessively-never show favoritism or become romantically involved with a student in your class-make eye contact with your students as much as possible-find a style that is comfortable for you-be aware of different learning styles, gender differences, cultural differences

5. Ability to evaluate fairly and consistently(*covered in workshop Thursday, September 9thEffectiveGrading Practices in Biology, Lisa Prichard)

In order for you to evaluate student performance effectively you must have first given the studentclear and concise instruction on the expectations of all work, whether written, oral or acquisitionof a particular skill.

Then you must be fair and consistent with your evaluation and not change your expectations afterthe fact.

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a. Common strategies: mark work and return quickly give only constructive feedback correct student work so you will encourage them to learn and participate; use a positive

reward system decide if your marking will be a holistic approach or very specific for certain criteria and

make sure you inform students before they produce the assignment try different methods to promote positive performance practice consistent marking by working in groups, check and discuss possibilities

Appendix A - Sample Format for a Session Plan

Course number: ____________________Title of Lab: ____________________________

Learning objectives:

1. __________________________________________________________________2. __________________________________________________________________3. __________________________________________________________________

Major points to be covered:

1. __________________________________________________________________2. __________________________________________________________________3. __________________________________________________________________

Minor points to be covered:

1. __________________________________________________________________2. __________________________________________________________________

Audiovisual or props needed: ______________________________________________

Supplementary handouts ___________________________________________________

Comments about this session (follow up questions to be answered; ways to improve effectiveness of thelab; areas to review next time: possible exam questions):

_______________________________________________________________________

_______________________________________________________________________

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Appendix B - Questioning Skills

Levels of Questioning

Knowledge Comprehension Application

Analysis Synthesis Evaluation

If most of your questions are at the knowledge level, many students will become bored.

If most of your questions are at the synthesis or evaluation levels, many students will be unable toparticipate and will become quickly discouraged.

Vary the levels and slowly introduce higher level questioning of synthesis and evaluation.Avoid ambiguous questionsAmbiguous questions frequently can be avoided by using the corresponding written question as amodel. While you might use name, write or devise in a written question you might use what,how or why in an oral question

Avoid yes and no questionsInstead of asking is carbon dioxide considered a pollutant? try rephrasing it to Why is carbondioxide a pollutant?

Avoid double-barreled questionsQuestions that pose two problems simultaneously are confusing and should be avoided. Forexample What is the difference between meiosis and mitosis, and how do these processesfunction in the life cycle of a fern?

Exercise:

Prepare a 10 minute talk that would outline the main objectives for the lab which you are teaching.

Go back over the talk and develop 3 questions that are key to the students understanding of the labmaterial. Use the objectives of the lab as your guide for the key areas on which to formulate yourquestions. Use guidelines from above to determine the level of questioning required.

Try to fit these questions into the context of your talk.

To practice getting students to answer these questions effectively, for each question develop a series ofquestions that would lead the student to get to the correct answer.

Exercise:

During the lab, circulate among your students and check on level of understanding and knowledge of theskills to be performed.

Ask hows it going?

Go back to original questions from prelab talk and check for understanding again? If they are not able torespond effectively, use a series of questions to lead them to the correct response. Remember toacknowledge when they get the correct answer. If they are incorrect, try to rephrase the question.

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Appendix C - Developing an Investigative or Guided Inquiry Lab

Controlled exercises are often thought of as verification exercises. Often valuable in the early stages of acourse where emphasis is on skills, technical accuracy, making observations, transforming data anddrawing conclusions. Generally they can be completed in a short period of time and there is a knownoutcome. There is an ease for set up and repeatability from year to year. Are they the best way for

students to learn?

Probably not, but unfortunately, they are a fact of life in many large, introductory courses because of theshear volume of students needing a laboratory experience. The disadvantage of controlled exercises is thatstudents often do not like them, finding them dull and tedious. They find the pre-lab work a meaninglessritual, the introductory talks boring and the controlled exercises as lacking personal satisfaction orconnection to their real world.

How would you could you develop this into a guided inquiry-based or investigative laboratory?

Requirements for Fermentation in Yeasts

Yeasts are simple unicellular organisms related to mushrooms, molds and mildews. They are called

heterotrophs because they do not carry on photosynthesis, but obtain their food from outside source. Theyare also classified as facultative anaerobes as they can live in environments with (aerobic) or withoutoxygen (anaerobic). Under aerobic conditions, yeasts use sugar for energy (cellular respiration) to live andproduce carbon dioxide and water as by products. Under anaerobic conditions, yeasts carry outfermentation to produce alcohol and carbon dioxide.

During the process of glycolysis and fermentation, yeasts use sugars, but not all sugars are used at the samerate? How do the following experimental procedures affect the rate of fermentation in yeasts?

Procedure:1) There are four major treatments:Treatment Yeast Boiled Yeast Sugar Water

I 10 ml - 5% glucose -

II 10 ml - 5% sucrose -III - 10 ml 5% sucrose -IV 10 ml - - Distilled water

2) Obtain two plastic fermentation vials, one large and one small.3) Add 10 ml of yeast suspension (boiled yeast for treatment III) to the smaller vial.4) Finish filling the smaller vial to its brim with sugar solution or with distilled water as designated

for your group.5) Hold the small vial upright. Invert the large vial so that the bottom side is upward and lower it to

cover the small vial.6) Hold the two vials tightly together at their ends and invert the apparatus so that the small vial is

now upside down with the larger vial. As C02 is produced by the process of fermentation, it willcollect in the upper portion of the small vial and the yeast mixture will be pushed downward and

out into the larger vial.7) If there is an air space at the top of the small vial, measure its length using a millimeter ruler and

use this measurement as the zero point.8) Measure the length of the gas column at 5-minute intervals for up to 45 minutes.9) Record your readings in the table in your manual.10)Record data for all lab groups. Average the data for each time period and place group data on the

blackboard.11)Plot the graph on graph paper.12)What are the effects of the different experimental regimes on the rate of fermentation in yeasts.

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13) Present the results in a full lab report as discussed in previous labs.Appendix D Sample Flowchart

Prepare cells, Steps 1-6

Take 5 aliquots, Steps 7 & 8

Fix 5' on ice,Step 9

Cool on ice 5',Step 8

#3#2#1 #4 #5

Wash bycentrifugation andresuspension into

final 25 lStep 10

AddsodiumazideStep 11

Addsodium

azideStep 11

Add FITC anti-mouse IgGStep 12

Keep on iceStep 13

Warm 15' in a 37C waterbathStep 13

Fix with cold fixative 15' on iceStep 14

Wash twice by pelleting at speed 5 for 3'and resuspending in 1 ml PBS

Pellet and resuspend in 50 l PBSStep 15

Put 10 l of each suspension on a microscopeslide, cover with a coverslip and count 50fluorescent cells from each slide for

staining patternStep 16

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