Are big classes the problem?

When I ran Physics Today‘s Search and Discovery department, I’d interview about 10 physicists a month. Most interviews took place on the phone, but occasionally I met physicists in their offices.

I prefer in-person interviews. Besides the face-to-face interaction, there’s the opportunity for interviewees to move over to their blackboards and write down an equation or draw a diagram. I remember with gratitude Victor Yakovenko explaining Majorana quasiparticles to me at the University of Maryland and Michael Hesse explaining magnetohydrodynamic reconnection at NASA’s Goddard Space Flight Center.

Recently, I’ve come to realize that those in-person interviews resembled the tutorials I received as an undergraduate at Imperial College London. Once a week, students in groups of three would meet their assigned tutor—invariably a member of the faculty—in his or her office. There, they’d discuss the answers to a problem sheet that one of the lecturers had set. And, if time allowed, they’d talk about other physics topics.

The problems were meant to test students’ understanding of the courses. Students had a few days to work on the answers. If they couldn’t solve the problems, the tutor would explain what they hadn’t grasped—by moving to the blackboard and writing down equations or drawing diagrams.

Learning physics entails understanding concepts far more than it entails memorizing facts. Because one student’s path to understanding may be different from another’s, the personal guidance that the traditional tutorial provides is ideal for teaching physics. I was glad to hear from Steve Blau, one of my Physics Today colleagues, that the tutorial method—or something close to it—was practiced at the small liberal arts college that he attended, Haverford, and the one where he taught physics, Ripon.

But it’s not the norm at big US universities. There, introductory courses are so large that mobilizing a department’s entire faculty would not yield tutorial sessions of one professor and three students. Instead, those big universities rely on graduate students as teaching assistants.

Some online innovations, such as massively open online courses , widen access to lectures. Others, such as learning management systems, improve administrative efficiency. Both outcomes are worthy. But as far as I can tell, no one has devised an online tool that matches small-group instruction in its effectiveness and, indeed, in the pleasure it adds to teaching and learning.

Make them smaller

If large classes impede learning, then one obvious solution is to make them smaller. Hiring more professors would achieve that goal, but at significant expense. A better way, I contend, is to reform the system that creates large classes in the first place: American universities should scale back the number of general education courses they require students to take.

That proposal might seem heretical. After all, employers say they want well-rounded graduates who can not only frame and solve problems, but also express themselves clearly and persuasively—just the sort of employee that a traditional US university education is meant to produce. Exposing nonscience majors to science is also a good thing. Jon Miller, who directs the University of Michigan’s International Center for the Advancement of Scientific Literacy, has found that the principal source of Americans’ scientific literacy is not the popular press, TV, or other media, but the science courses they take in college.

Nevertheless, I think it’s time that US universities reconsider the undergraduate degree. Hong Kong’s government did so . Last year, the territory’s public universities switched from the specialist, British-style three-year degree to the US-style four-year degree—but with a crucial and significant difference. Whereas US undergraduates typically spend half their time taking subjects outside their majors, Hong Kong undergraduates spend one quarter.

My proposal amounts to redistributing students among subjects. Do the numbers work out? Yes, I think so. The University of Delaware, my wife’s alma mater, has a total of 15 747 undergraduates and 1128 full-time faculty. Its 65 academic departments offer 147 majors. In the spirit of the physicist’s spherical cow , consider the case of evenly distributing the students and faculty members among the departments. Each department’s 17 professors would then be responsible for teaching 242 students per calendar year. Each professor could tutor students in groups of four.

There’s another advantage to reducing general education requirements. Students choose their majors out of interest; presumably they’d prefer to take more in-major courses than the current system permits. My wife did. Professors would benefit, too. They’d no longer face huge classes of students, a large fraction of whom are taking the course because they have to, rather than because they want to.

If my simplistic analysis has missed something or if you disagree with its premises, please leave a comment. My goal in writing this column is to start a debate—not to win one.