A feature article in Harvard Magazine (March-April 2012) asserts that the traditional lecture method of instruction is giving way to something far better. The author, Craig Lambert, waxes euphoric over this development. He tells how Eric Mazur, professor of physics at Harvard, had an “epiphany” that led him to overturn his teaching methods. Finding that his students dutifully memorized formulas but lacked a grasp of fundamental physics concepts, he had them engage in “peer instruction” during class and saw dramatic results.
Mazur began experimenting more with peer instruction, gathered data on the results, published a book on the subject, and became a coveted speaker on the subject around the world. Other professors have followed suit, replacing lectures with “innovative” methods. According to Lambert, “active” or “interactive” learning is in, and “passive” learning out. “Interactive pedagogy,” he writes, “turns passive, note-taking students into active, de facto teachers who explain their ideas to each other and contend for their points of view.”
Lambert’s error (by no means his alone) lies in his assumption that students who listen to a lecture are less active than those who confer with each other. The reverse may be the case. In treating the lecture as an unwanted relic of the past, as the locus of passivity, we may set ourselves up for serious loss.
When a teacher or professor gives a lecture (including a physics lecture), he or she is not only delivering information, but also shaping, questioning, and recasting it. A lecture is a work of imagination and insight as well as an exposition. The student listening to the lecture may put it together in his mind, relate it to the reading or to specific problems, think of questions, enjoy the lecturer’s style, and more. A single phrase in the lecture may lead the student to an insight; one insight might lead to another. Lectures are not always this invigorating, but if they’re reasonably good, a student can find room for rumination in them. In addition, they offer respite from peer noise. There is plenty of time for talking with peers; during the lecture, this is not necessary.
Peer instruction, by contrast, can deaden the spirit and lower the level of instruction. Many subjects require quiet, extended thought; if there is no room for this in the classroom, if the room is usually “abuzz” with students talking to their neighbors, headaches may increase and insights decrease. Although students look active in such a situation (to outsiders, at least), they may be insidiously passive—relying on peers’ explanations instead of thinking about the problems on their own, or providing explanations to peers who haven’t done their homework. Of course, peer instruction need not always be stultifying—but it can be.
Oh, but the research shows… Let’s stop right there. Education research rarely “shows” what the researchers or the media claim it shows. (See, for instance, an egregiously flawed study that purportedly shows the superiority of “deliberate practice” to the lecture method.) Moreover, to determine what “works,” you need to establish what you want to accomplish in the first place. Otherwise the findings may not apply to your goals at all. (This point often gets lost in education discussion.)
If you wish to teach a subject richly, if you want students to grapple with its fundamentals and tackle difficult problems, then you need to present these fundamentals and problems, period. There are different ways to do this; the lecture is a particularly appealing method, since it brings everyone together in the same room. It brings responsibilities; students must learn to take the lectures in and work with them in their minds. If they don’t know how to do this, if a lecture strikes them as boring because it’s a lecture, then they need more practice listening to lectures, not less.
In addition, a lecture sets an example of scholarship. A fifty-minute lecture approximates certain scholarly articles in scope and length. When listening to the lecture, students learn what kinds of topics might fit into that time frame. They recognize interesting explanations and examples; they light up over an insight; they enjoy a good joke or allusion. The lecture carries a certain honor; just as the students listen respectfully to the professor, they imagine a time when they themselves might speak to an audience. The challenge (for professors and students alike) is to live up to that honor, not destroy it.
So, if we want students to grasp both the substance and shaping of a subject, we want something like a lecture. Of course, we also want them to do well in the subject and to understand it. How to accomplish all of this? Well, first of all, take them into the lecture format gradually, during the K-12 years of school, so that they know what to do with it. Second, pair it with a contrasting instructional format, such as a seminar or discussion group. (The lecture is usually insufficient on its own.) Third, provide books, problems, and other resources.
Don’t get rid of the lecture. Properly prepared, delivered, and received, it gives students something substantial and allows them to think about it. At its best, it offers insight and illumination; it may stay in the memory, for years, as both detail and gesture. Better not to spurn such gifts.