thinlens

Reposted from my old blog.

From undergrad through my PhD, I learned physics in traditional lecture courses, and I very much enjoyed it. Over the years, whenever I’ve heard tell of the magic of active learning it’s been like nails on a chalkboard to me. I originally set out to write a whole-hearted defense the traditional lecture while violently skewering active learning, however in reading some of the active learning literature, I came to see they make some good points, often with a great deal of data on their side. Based on my experience as a TA, I still believe that active learning approaches like MIT’s TEAL introduce more problems than they solve, but I’m convinced it’s worth at least engaging with the issue. This first post is about how active learning was introduced to physics. The second will be about how it works in practice.

Intro physics is hard, even at the statiest of state schools. Why are these first physics courses so challenging? In many subjects, students might begin a course knowing very little about the material, but in physics, Halloun and Hestenes (HH) argue that beginners know a great deal about the topic; the problem is everything they “know” is wrong. In a pair of extremely well cited papers ([1] and [2]), HH argue that students generally begin intro physics courses with strongly held essentially medieval beliefs about kinematics and dynamics, and traditional lecture courses are unable disendow them of these misconceptions. The implication is that students learn to perform calculations about falling projectiles and inclined planes using F=ma and x=½ a t² and E = ½ m v², but they are unable to integrate these concepts with their original common sense, leading to poor conceptual understanding when asked questions which require more than grasping for formulas.

These finding ignited efforts at Harvard, MIT, ASU, and many other universities to reimagine Physics 101 to promote active instead of passive learning. In 1990, after years of polished lecturing for Harvard’s Physics 11, Eric Mazur asked his students a conceptual question off the cuff, and received only blank stares [3]. “How should I answer these questions according to what you taught me”, a student asked. Discouraged, he asked students to discuss, and within just a few minutes, students agreed on the correct answer. Mazur has become one of the leaders of the active learning movement in physics, and MIT has formalized these techniques into a course known as TEAL: Technology-Enabled Active Learning.

Compared to a lecture course, TEAL seems downright bizarre. Students sit in small groups around circular tables in a specially constructed room with white boards covering the walls. Instructors lecture from PowerPoint slides interspersed with conceptual questions, demos, and small group problem-solving sessions. Trials showed both high- and low-achievers taking the TEAL course learned more than their peers taking traditional lecture courses [4]. Based on these results, TEAL physics has become mandatory for all MIT freshman (except those placing into the advanced track). Clearly MIT should be lauded for its pursuit of better teaching and learning.

But goals are one thing, reality is very much another. In my next post, I’ll discuss the good, the bad, and the ugly of active learning put into practice, based on my experience as a TA.

[1] Halloun, I. A. and Hestenes, D. (1985). The initial knowledge state of college physics students. American Journal of Physics, 53, 1043. [2] Halloun, I. A. and Hestenes, D. (1985). Common sense concepts about motion. American Journal of Physics, 53, 1056. [3] Lambert C. (2012) Twilight of the lecture, Harvard Magazine, March-April 2012 [4] Dori, Y. J., Belcher, J. (2005). How does technology-enabled active learning affect undergraduate students’ understanding of electromagnetism concepts? The journal of the learning sciences, 14(2), 243–279.

Posted by Abraham