CHAPTER 3 : SPECIAL TEACHING TOPICS FOR TAs

LAB SECTIONS AND THE TA

There are some general tips which can be provided about leading all lab sections despite the unique demands of leading a lab in each of the various disciplines. Chemistry labs, for example, place different demands on a TA than do geology, physics or biology labs. Whatever type of lab you're responsible for leading, you can help to ensure your success by thinking back to and utilizing the Model of Instruction which was presented earlier in this manual. To reiterate, succeeding as a lab TA can be as easy as PIE.

  1. Plan what you're going to do.
  2. Implement what you've planned.
  3. Evaluate what you've done.

PLANNING LAB SESSIONS

The most important thing you can do to ensure that your lab sessions run smoothly is to be well-prepared. Your preparation, prior to the start of the quarter, should include being acquainted with the storeroom of the lab so that time won't be lost during a lab looking for necessary equipment or materials, and if applicable, knowing the location of the first aid kit, basic first aid rules, and procedures for getting emergency assistance.

Basic weekly planning for your lab section might include the following.

  1. KNOW EXACTLY WHAT THE STUDENTS ARE SUPPOSED TO LEARN AND WHY they have to learn these things. This may come in handy when your students start to wonder why they're doing what they're doing.
  2. PERFORM THE ENTIRE EXPERIMENT IN ADVANCE. There's no guarantee it's going to work as advertised in the lab manual (if there IS one). By going through the lab yourself, you'll be familiar with some of the stumbling blocks that your students may confront and you'll know the subtler points of the coming lab.
  3. READ AND STUDY THE THEORY on which the experiment(s) are based. Your thorough understanding of the theoretical aspect of the lab should be useful to you in handling most student questions which don't deal with concrete parts of the experiment(s).
  4. RESEARCH THE RELEVANCE OF THE EXPERIMENT, both the technique being taught and the applications of the theory being demonstrated.
  5. DECIDE HOW TO INTRODUCE THE LAB MOST EFFECTIVELY. Before students get underway with the day's lab, will they need you to demonstrate the procedures that they'll be following? Is a handout with written instructions in order? Do you want two students in the class to demonstrate the experiment to the rest of the class? Will a 15-minute lecture about the theory and intent of the lab suffice? Your initial introduction to the lab or the day's first activity can set the tone and motivation for the rest of the lab.

IMPLEMENTING WHAT YOU'VE PLANNED

Below are some suggestions for effectively doing what you've planned for your lab.

  1. TELL YOUR STUDENTS THE PURPOSE OF EACH LAB and what you specifically expect them to be doing.
  2. ASSESS WHETHER OR NOT STUDENTS ARE AS PREPARED FOR THE LAB AS YOU EXPECT THEM TO BE. If you've asked your students to complete some readings or activities prior to the lab you would be wise to find out whether they have done so. You can do this in a variety of ways, e.g., asking a few pointed questions or having students break into small groups for 10 minutes at the beginning of the lab while you circulate, asking for questions that students may have about their preparations. If no one seems ready to do the experiment AND it's costly to conduct, you may need to reschedule the lab. Otherwise, you can use this informal assessment to clear up areas of confusion before the lab gets underway.
  3. SHOW STUDENTS HOW TO HANDLE AND CARE FOR EQUIPMENT THEY'LL BE USING. This should serve to eliminate the unnecessary breakage or repetition of common questions about a particular piece of equipment.
  4. PREPARE HANDOUTS WHICH AMPLIFY THE LAB OR ANY DIFFICULT CALCULATIONS. Handouts can be efficient aids for a weekly lab. Make and use them creatively.
  5. PROVIDE STUDENTS WITH ANY NECESSARY INSTRUCTIONS FOR COMPLETING THE LAB. This can be done with a handout, with words, or by referring them to the appropriate page of a lab manual.
  6. DEMONSTRATE ANY PART OF THE PROCEDURE WHICH MAY BE PROBLEMATIC. Again, taking the time to anticipate difficulties before everyone starts working may save you from providing countless repetitions of a minor procedure.
  7. ENFORCE LABORATORY RULES, especially if safety is an issue. You should also adhere to the rules since students view you as a model for lab behavior. Making safety concerns known is a necessary first step in avoiding serious problems. In addition, stress lab courtesy. Be sure to have students clean their lab area before they leave. Also, report breakages in the lab as soon as possible and set broken apparatus aside, clearly marked for other students and TAs who will be using the lab after you.
  8. INFORM YOUR STUDENTS OF THE APPROXIMATE AMOUNT OF TIME DIFFERENT TASKS WILL TAKE so that they can pace themselves accordingly.
  9. PROVIDE STUDENTS WITH LABORATORY HINTS-helpful information, sample data, the derivation and use of any typical formulas and calculations of sample lab problems. Such information can smooth out the process of completing a lab.
  10. INFORM STUDENTS OF THE PROCEDURES AND RULES FOR WRITING UP AND SUBMITTING LAB REPORTS or results of experiments. If you are as explicit as possible about what you expect in the way of written work, you can save yourself from the post-grading complaints and hassles which students can inflict on an unprepared TA.
  11. POINT OUT INTERESTING HISTORICAL ASPECTS OF THE EXPERIMENT whenever possible (e.g., "Galileo did this whole thing using a cathedral lantern for a pendulum and his pulse for a watch!"). Historical anecdotes can increase student motivation for the lab by adding a new perspective to their tasks (instead of being motivated soley to receive course credit) as well as breaking up the routine of the section.
  12. CIRCULATE AMONG YOUR STUDENTS WHILE THE LAB IS IN PROGRESS and be available to give assistance and answer questions. As a lab TA, you have the opportunity for an unusual degree of involvement with student learning. You can observe your students at work and give them help where it's needed. Don't wait for students to ask you questions since they may be a little hesitant(especially early in the quarter). Ask a few strategic questions of your own in order to figure out what students do/do not understand (e.g., "Once you plot those points on your graph, how are you going to find the best straight line through them?", or "Why do they tell you to make measurements with the current going both ways through the coil?"). Be aware that there is a difference between hovering around students, intimidating them, and circulating around being friendly and letting them know that you want to interact and help with the lab.

EVALUATING WHAT YOU'VE DONE

As the lab section draws to a close, you'll want to assess your success as well as that of your students in the lab. As in most situations, evaluations can be conducted both formally and informally.

Formally

  1. READ AND EVALUATE STUDENT LAB WRITE-UPS to assess individual or group success in a) completing the lab, b) gathering the appropriate data, c) drawing reasonable conclusions from the data, and d) following designated procedures for the lab report.
  2. ADMINISTER FREQUENT QUIZZES to inform you and your students of their understanding of the facts, concepts, principles, procedures, etc., that you expect them to be acquiring in the lab (see "Testing and the TA" for tips on quiz construction).
  3. ASK FOR WRITTEN FEEDBACK ABOUT YOUR PERFORMANCE AS A LAB TA. You can gather MID-QUARTER FEEDBACK by distributing a short questionnaire to your students around midterms. The intent of mid-quarter feedback is to provide you with information reflecting student opinion about specific aspects of your section, e.g., clarity of presentation, relevance of material, willingness to respond to questions. These brief surveys can also provide some global reactions to the course in general. By reviewing these questionnaires right away, you may be able to make changes that will affect the students from whom the feedback was obtained.

Informally

  1. LISTEN TO QUESTIONS THAT ARE ASKED AND PROBLEMS THAT ARISE during the lab. If an individual asks a critical question or experiences an important problem, you can draw this to the attention of the entire class. Student questions help to pinpoint difficulties in coping with the lab.
  2. ASK QUESTIONS WHICH WILL LET YOU KNOW IF STUDENTS UNDERSTAND WHAT'S GOING ON. This can be an effective means for assessing student progress in the lab.
  3. FREQUENTLY ASK IF STUDENTS ARE UNDERSTANDING WHAT YOU'RE PRESENTING OR ASKING THEM TO DO. Student response to this or similar questions may serve as an informal barometer about the perceived pace and clarity of your lab presentations and instructions.