Fall term is now past its midpoint. Last week I gave my first midterm exam (a second one will be administered on the last day of classes), and the class average was remarkably close to that of the midterm which I gave two years ago, when I taught the same course. Back then enrolment was 198, this time around it is over twice that.
So, how are things going thus far ? Well, as I wrote above, midterm average (74.8%) was very nearly the same as two years ago (74.4%), even though exam was multiple-choice this time, while back then it was problem based.
How is the course going, in general ? I am reasonably satisfied at this point.
I am slowly getting more comfortable with the large classroom setting, which created some problems early on. Granted, I still wish I had my white board, but I think I am better now at using the overhead projector. I am receiving more questions during lecture, and I do not have to ask as much as I did early on for the person to speak louder — maybe they are beginning to feel a tad more confident.
But the one aspect that is markedly different, with respect to the last time I taught this course, is the significantly smaller number of students who seek help from me after class, either by sending me e-mails or by coming to my office. Two years ago I had them lined up outside my office after class, as well as popping in at random times or sending me e-mails, asking me to go through class examples or homework problems one more time. I was expecting the same to happen this time around, and that was actually something that worried me quite a bit, given the sheer size of this class. And yes, they still do it, they are still needing help but, much less than I expected. The graduate student in charge of help session is also seeing the same.
It would appear that, while the results are all in all the same, students have, on average, an easier time “digesting” the course material on their own than in the past.
1) I am teaching in my same, usual way (the only one I know)
2) the material is the same
3) assignments and the midterm are not easier, in fact homework is probably harder
4) no extra help sessions are available to students
5) textbook is the same
the only possible explanation for the above (of course, this is only the middle of the term and things could still change) is the use of online homework, which I have adopted this time for the first time ever . I have to admit it, I am impressed. It seems to work, and work well. The main advantage, compared to having students write solutions for a few problems, is that because they only need enter a numerical value, or a formula, I can assign a lot more problems per week (ten is a typical number).
Now, is the key to learning physics just working out a lot of problems ? I would have to defer to physics or science education experts, but I think that there is no question that practice helps. As argued by Freeman Dyson, in his book entitled “Disturbing the Universe” (perhaps a bit of an exaggeration.. I mean, OK, four hundred students is a lot, but still…), trying to lean physics or math without solving a lot of problems is equivalent to trying to learn a language just by studying its grammar, without actually practicing with conversation.
I have always been reluctant to recommend students to work out a lot of problems on their own, because it seems like a waste of time. A lot of the practice problems that one finds at the end of a chapter are very similar, and it does seem overkill, especially when one is trying to do well in five different courses at the same time. I have always thought that trying to understand the basic laws and formulae by focusing on a relatively small number of practice problems and examples would be sufficient, together with a thorough, methodical study of the theory. But maybe I have been wrong, namely I have been underestimating the importance the reinforcement that comes from sheer practice. Maybe learning is not the deep, complex and sophisticated intellectual exercise that we would like to believe it is, after all.
Gotta run to class. Stay tuned.
 Admittedly there is another possibility, namely that they may have spoken to students who took the course with me in the past, and these may have told them not to bother asking questions…