The Education Session at the 1999 CASCA AGM,
Saint Mary's University

Sometimes it seems like astronomy is almost too easy to teach. The subject is full of unusual concepts and dramatic images, the math level is often not too demanding, and nearly everyone in the classroom is there because they chose to be. It's quite a contrast to the challenge of motivating a surly bunch of non-majors in a typical first-year service course in physics. But it's easy to be mislead into thinking that, because the students seem keen, attendance is good, and the marks are high, much actual learning is taking place. It's very sobering to give your class a diagnostic test at the start and again at the end of term, and see how many fundamental misconceptions persist, even after weeks of your best and most engaging lecturing. What happened?

At the education session in Halifax this year, Douglas Duncan (University of Chicago and AAS Education Office) provided some fascinating insight into this question in a workshop on "Excellence in Teaching". He began by assuring the audience of >60 that is possible to improve one's teaching, and spoke briefly of being aware of a number of common behaviours which don't help the learning process. Like a guilty sinner at a revival meeting, I confess I found myself admitting my guilt as some of these "sins" were read out. Dr. Duncan stressed the importance of setting goals for a course, sharing those goals with the students, making sure the course is designed to meet those goals, and then trying to assess the success in meeting them.

The workshop then focused on how to move away from the traditional lecture format in order to help students better develop critical thinking skills, and to increase their involvement in learning. The major challenge to overcoming student misconceptions is their resistance to change. Old notions die hard! Students have to try their own ideas first, and find them wanting, before they are likely to replace them with concepts we try to teach. Dr. Duncan described the "weekly challenges" he uses in a large breadth requirement course for first-year non-science majors at the University of Chicago. The challenges are based in part on the ideas of "peer instruction" put forward by Harvard physicist Eric Mazur. Each challenge is a simple experiment with a decidedly non-intuitive result. The experiment is set up, but not performed, in the last 20 minutes of a 90-minute lecture on a Tuesday. The class splits into groups of 3-4 to discuss the challenge and to make a prediction. The predictions are collected at the start of class on Thursday, and then (and only then) is the experiment actually carried out. This turns out to be a very effective way to encourage learning; Duncan reported that it was not uncommon for groups to stay behind well after the lecture period, "lost in discussion and argument", and to try their own versions of the experiment outside of class time. Just how effective these challenges could be was very well shown by actually presenting us with one such challenge - to describe how we would perceive the colours of things in the room when illuminated solely by a yellow sodium-vapour street lamp. There were quite a number of animated discussions, even among us hardened and sophisticated scientists!

I found the workshop to be an extremely useful and interesting session. It has made me seriously think about what and how students learn, and about new ways to try to help them. I've since adopted Mazur's methods this year in my first-year physics course, and have begun to design a set of "weekly challenges" for the one-semester stellar astronomyy course coming up in January. I'd like to take my hat off to Doug Duncan for a most excellent presentation, and to the LOC at Saint Mary's for one of the best education sessions yet.