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Those of us who teach at large universities typically teach the 'lecture' part of the course, and the laboratory part is taught by graduate student teaching assistants. The success of the class as a whole involves both parts, so the integration of lecture and lab and the interaction of the professor and TA are important elements of the course.
When I discuss teaching issues with colleagues at peer institutions, one of the questions I ask is: "Do you visit the lab sections for your course?"
I am not talking about the large introductory courses that may have tens of lab sections taught in remote buildings at all hours of the day and may contain students from various sections of the course. When I teach a large introductory level course, I like to know what is going on in the labs in terms of topic/activities each week, but there is no way I can visit the labs.
The courses for which the question about visiting is most relevant are those that typically have 1-2 lab sections that are held in a location not too distant from faculty offices. There may be 1-2 teaching assistants, in many cases the instructor's own graduate students. Most of my courses have more than one lab section (and in some cases more than one TA), so I don't really have time to visit the labs, but it would at least be humanly possible for me to visit the labs. But do I visit the labs?
I have found that there are pros and cons to visiting the labs for my courses.
If I spend enough time in the lab, I can get a better sense for how the students (individually and as a group) are doing in the class. Who is struggling? Who would like more of a challenge? What concepts are not getting through via in-class lectures and activities?
Students have additional opportunities to talk to me and ask questions, and there is time to answer questions at length.
I can refer to lab activities in a more informed way in class. It is better to be able to say in class "As you saw in lab on Tuesday.." rather than "As you may have seen in lab on Tuesday.." or (worse) "As you were supposed to have seen in lab on Tuesday..".
Students will have additional evidence that I care about the course and my students.
The TA may feel undermined. Am I visiting the lab because I don't trust the TA's teaching abilities or knowledge? Perhaps I am a control freak.
The students may feel nervous if I am looking over their shoulder and popping in at unexpected times. They might feel more comfortable around the TA, but may be anxious if I see them being perplexed by a lab activity. Will I think they are stupid?
I don't have time to visit the labs.
Ideally, the pros will surpass the cons, I will have infinite time to stroll into the lab sections, I will have a comfortable working relationship with the teaching assistants, and the students will all be happy and motivated seekers of knowledge. If only.
I used to visit the labs for my courses, but I found that the cons of doing this were outweighing the pros. Some teaching assistants definitely felt undermined, and thought I was checking up on them or not trusting them to explain things correctly. Also, some students were reluctant to admit they were confused when I asked if anyone had questions. Perhaps they were only temporarily confused, and the moment I chose to visit the lab was just at that time. This caused stress. So, my visits became less frequent, and in some (most?) terms, I don't visit the labs at all. This fact shocks some of my friends who teach at small colleges and who teach both lecture and lab (or make no distinction between these two elements of their courses).
I am, however, very involved in construction of the lab activities, and I try to integrate class and lab each week so that lab is not a random disconnected activity that the students go off and do in another room in the building.
This works OK, and this is also what most of my colleagues do. Most of us don't visit the labs, primarily owing to lack of time. Those who do visit labs do so because (1) there is one lab section that immediately follows or precedes the lecture part of the class, in some cases in the same room, making it easier to be involved in the lab; or (2) the TA really is inadequate. I have never been in situation #1, and, in my experience, situation #2 is extremely rare.
7 months ago