John Hader passed this link to an NPR story/podcast about research related to lectures a few weeks back, which I’ve been saving while making plans to unveil it to my students.
Hestenes got the idea for the series when a colleague came to him with a problem. The students in his introductory physics courses were not doing well: Semester after semester, the class average never got above about 40 percent.
“I noted that the reason for that was that his examination questions were mostly qualitative, requiring understanding of the concepts rather than just calculational, using formulas, which is what most of the instructors did,” Hestenes says.
Hestenes had a suspicion students were just memorizing the formulas and never really getting the concepts. So he and a colleague developed a test to look at students’ conceptual understanding of physics. It’s a test Maryland’s Redish has given his students many times.
Here’s a question from the test: “Two balls are the same size but one weighs twice as much as the other. The balls are dropped from the top of a two-story building at the same instant of time. The time it takes the ball to reach the ground will be…”
The possible answers include about half as long for the heavier ball, about half as long for the lighter ball, or the same time for both. This is a fundamental concept but even some people who’ve taken physics get this question wrong…
While most physics students can recite Newton’s second law of motion, Harvard’s Mazur says, the conceptual test developed by Hestenes showed that after an entire semester they understood only about 14 percent more about the fundamental concepts of physics…
The test has now been given to tens of thousands of students around the world and the results are virtually the same everywhere. The traditional lecture-based physics course produces little or no change in most students’ fundamental understanding of how the physical world works.
“The classes only seem to be really working for about 10 percent of the students,” Arizona State’s Hestenes says. “And I maintain, I think all the evidence indicates, that these 10 percent are the students that would learn it even without the instructor. They essentially learn it on their own.”
He says that listening to someone talk is not an effective way to learn any subject.
“Students have to be active in developing their knowledge,” he says. “They can’t passively assimilate it.”
This is something many people have known intuitively for a long time — the physicists just came up with the hard data. Their work, along with research by cognitive scientists, provides a compelling case against lecturing.
It arrived in my mailbox just as my student evaluations did, in which I found the overwhelmingly most frequent suggestion to be something like, “Discussion and student engagement are great, but it would be better if you just lectured more and simply told us what the readings mean.” And I get it–there’s a lot of value in a well done lecture; I don’t deny it.
Furthermore, there’s a satisfying simplicity to class performance that amounts to taking dictation (which is what I truly suspect most (not all) of the students who made that particular suggestion were asking for–a simpler, more straightforward path to a grade: listen, copy, memorize, repeat. It’s both efficient (for the student), consistent with what some (not all) of them expect schooling to be about, and pretty non-threatening. They figure they can do it or they can’t–it’s schooling as performance. (Just to be clear, I am not universally conflating a lecture based teaching approach with the kind of rote regurgitation approach described above. I recognize that they do not necessarily travel together, and that some of the students asking for more lecture were seeking better understanding and guidance, not merely lists of answers that they could regurgitate. In the student comments, though, that asked for more lecture, most of them included the phrase “just tell us what it (the reading) means.” It is that second part that I am particularly averse to endorsing and particularly interested in disrupting as an expectation of what learning (particularly in higher ed environments) entails.)). And there is an attractiveness about simplicity, especially for stressed out and thinly spread people (like many of our students).
While discussing the evals with my beloved (an educator par excellence, and the person from whom I’ve stolen all of my best ideas), she suggested that I make those critiques front and center in my classes–presenting them to my new groups, saying, “Here’s what students say about my classes. Here’s what they say the want. And here’s why I’m not going to provide that.”
I thought it was a great idea and I plan on doing it (though I’ve decided to let them get into the classes a little bit and see how they work first), and when I do, I’m going to play this story for them.
Because what they want is not always what they need, and what they think is best for them is not always what actually is best for them.
h/t to Hader for the pointer.
This is a timely post. At CAST’s first Thursday Teaching Talk (Cookies and CAST) this past week, we discussed the exact same topic. I look forward to reading the full story. Speaking of CAST TTT’s, our next Thursday Teaching Talk (Nuts and Bolts) will be on Thurs. 2/23 at 3:30 in 1046. We will examine the question, “What do you do when…?” CAST’s other TTT (Technology Tools of the Trade) will likely return in late February or early March.