Inside Higher Ed has a short piece today on a lecture given to the Carnegie Foundation for the Advancement of Teaching by Carl Wieman on how to teach science. Though, from the sound of it, it was mostly about how not to teach science.
During the talk on Friday, Wieman said that traditional science instruction involves lectures, textbooks, homework and exams. Wieman said that this process simply doesn't work. He cited a number of studies to make his point. At the University of Maryland, an instructor found that students interviewed immediately after a science lecture had only a vague understanding of what the lecture had been about. Other researchers found that students only retained a small amount of the information after watching a video on science.
Another problem with the current structure of science education is that teachers try to get students to learn "key concepts" from physics. "We think that physics has a few ideas that can be widely applied," he said. "So people test for those few ideas." Wieman says that students really only retain about 30 percent of those key concepts, so this approach simply does not work.
He did offer some constructive suggestions, but they have their own problems:
While Wieman said that he does not have all the answers for restructuring how science is taught, and added that he is still trying to figure out the best way to teach, he did offer suggestions. First, reduce cognitive load in learning by slowing down the amount of information being offered, by providing visuals, and by organizing the information for the student as it is being presented. Second, address students' beliefs about science by explaining how a lecture is worth learning and by helping the students to understand how the information connects to the world around them.
Everybody in the business agrees that "slowing down the amount of information being offered" will improve student retention. The problem is, we're rather tightly constrained in how much we can slow things down. Our intro physics sequence is a great tool for producing information overload in first-year students, and would probably work better at a slower pace, but we aren't free to do that-- the bulk of the students in the class are future engineers, and there's a long list of topics they need to see covered in only two classes. The pre-med class is even worse, but there, the content is set by the MCAT.
It would be great if we could spread the intro course material out over three courses rather than two, or the pre-med class over four, but that's not going to happen. Which means we're pretty much stuck with trying to do the best we can in the whirlwind-survey-course format.
Some global agreement from all of the science and engineering disciplines that everybody needs to slow down in the interests of more effective teaching would be wonderful. It would also probably double the length of time required to get a science or engineering degree, and nobody's willing to do that.
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i disagree with his: well, students only retain 30% of the concepts, so clearly that approach isn't working.
what's the alternative? teach little details and have students understand only 30% of those? that's even worse.
concepts are still the most important thing, imo. it's just the way the concepts are taught that is often the problem.
i really like some of the suggestions put forth in the comments on that article: smaller classes, real discussion, close reading, theoretical underpinnings and throw out the textbook.
I have the luxury of being able to teach a physics 1 & 2 sequence at a libeal arts school where I have NO such constraints. We have no physics, chem, or bio majors, so I have the luxury of being able to cover the topics I want at the pace I want. And I'm not sure I accept the defeatist attitude of "Oh this will never change". If it could be shown that students come out of my classes better able to understand basic physics ideas than the ones who spent two semesters being befuddled by a whirlwind of equations and end-of-the-chapter problems, why WOULDN'T universities decide that it makes more sense to offer a different kind of physics course? (Of course we can't replace the calc-based physics sequence for physicists and engineers, those folks still have to suffer... I'm talking about the "algebra-based" physics that many bio-majors take.)
As far as the MCAT goes... why do we let some commercial test-writing company decide what physics pre-med students need to know? When is the last time any THOUGHT was put into these issues?
I've got really mixed feelings on this one, and can see the points of both the current info-overload approach and the slow-and-deep approach. On one hand, I can really see the benefit of spending a lot of time on a few subjects and letting students become relatively accomplished on those subjects. It's motivating to become skilled, and it's important to see how the field works. On the other hand, one of the goals of an intro class is to give students the vocabulary to talk about and learn about a variety of subjects, even if they barely know anything about those subjects. People need to know that certain lines of research exist, and if we only talk about a few topics in detail, they'll be ignorant of the questions, not to mention the answers.
Perhaps what to do is to split the difference. Identify the topics that people merely need to know exist. Tell the students "we don't care if you really know much about these topics, but you need to know the vocabulary, so we're going to cover a huge amount of material in a short time. Mostly, you're going to have to memorize a bunch of facts and definitions." Then, find a small number of topics (say, 3 a semester) with deep, theoretically interesting properties, and teach them in parallel with the overview. Spend part of each class introducing a bunch of material shallowly, then spend the rest of the class continuing work on the ongoing topic. In AI, say, while quickly going over several chapters in the encyclopedic textbook, spend a month working on Bayesian networks, working examples, designing systems, considering scalability, learning, and real-life applications. Give pop-quizzes and homeworks focusing on the deep topics to increase retention. Then, after the class, they can use the techniques they learned about how to learn about a topic in the field in depth to apply to topics you didn't cover in depth.
what's the alternative? teach little details and have students understand only 30% of those? that's even worse.
catswym,
I think Wieman's idea is that if you teach fewer details the students will retain a higher percentage of them.
Maybe it would be better to actually get kids to learn these basic principles before they got to university?
As has been noted before on numerous other studies, if you don't get them seeing "science" properly by 2nd to 5th grades, you'll never get them to see it. the "scientific method" is not something that needs to wait until 6th grade before being presented.
For all the talk about improving kids abilities to read, just shoving more literature in front of kids reaches a limit. They can philosophize on moral implications of fictional characters or poetic imagery all they want, but reading science or history is reading for real understanding.
I teach physiology to first-year medical students, and I am sometimes shocked at their lack of conceptual understanding of basic physical science. For example, we were discussing thermoregulation last week, and some of the students were mystified by the notion that there are only two fundamentally different ways for heat to be transferred--either by direct contact of two molecules or by exchange of an infrared photon.
From the standpoint of medical education, it is much more important that students gain an intuitve grasp of these basic concepts than that they learn mathematical formulas by rote.
Thank you Joe Shelby. I agree completely. Our high schools are failures with regard to science education. Students also manage to complete high school without much in the way of writing skills. So, in my mind, most solutions to the science teaching problem in the university have to address the high school issues as well.
T
dr. dave: I have the luxury of being able to teach a physics 1 & 2 sequence at a libeal arts school where I have NO such constraints. We have no physics, chem, or bio majors, so I have the luxury of being able to cover the topics I want at the pace I want. And I'm not sure I accept the defeatist attitude of "Oh this will never change". If it could be shown that students come out of my classes better able to understand basic physics ideas than the ones who spent two semesters being befuddled by a whirlwind of equations and end-of-the-chapter problems, why WOULDN'T universities decide that it makes more sense to offer a different kind of physics course?
I don't think that it's impossible to change things, just that it's not nearly as simple as the article implies. It's not just a matter of deciding to teach fewer concepts in order for students to understand them better-- first, we need to make sure that the people in other departments who are depending on those courses are ok with having students come out with a better understanding of a smaller number of concepts.
As far as the MCAT goes... why do we let some commercial test-writing company decide what physics pre-med students need to know? When is the last time any THOUGHT was put into these issues?
I have no idea how the current system came about, but believe me, I'd be ecstatic if somebody got rid of the MCAT. It makes life easy for medical schools, though (and don't get me started on the med school admissions process...), so it's not going away any time soon.
Joe Shelby: Maybe it would be better to actually get kids to learn these basic principles before they got to university?
As has been noted before on numerous other studies, if you don't get them seeing "science" properly by 2nd to 5th grades, you'll never get them to see it. the "scientific method" is not something that needs to wait until 6th grade before being presented.
Absolutely.
Also, somebody needs to teach high school students to do algebra. Every time I see students writing:
1/(a+b) = 1/a + 1/b,
I want to bludgeon a math teacher.
(Not that I've been grading exams, or anything...)
The problem here is figuring out how to do the best we can with what we get from the high schools, working within the constraints provided by other majors and programs. We can work to change what's taught elsewhere, but that's going to be a slow process.
Some global agreement from all of the science and engineering disciplines that everybody needs to slow down in the interests of more effective teaching would be wonderful. It would also probably double the length of time required to get a science or engineering degree, and nobody's willing to do that.
Quoted for truth. The only real way I can see to get this sort of extension in study time is to start in with the college-level stuff in the final couple of years of high school. That notion brings up its own problems, I'm afraid, if enough of what I hear about education majors is really true.
1/(a+b) = 1/a + 1/b
Yikes! I'm not sure "slowing down" your physics lecture is going to help that kid...
I wish it was just one kid-- I get that mistake all the time.
Another great one if you want to see some mathematical flailing is to give students an expression like:
x = a/by
and ask them to solve for y.
Physics courses at the pre-engineer and pre-med levels are really courses in solving physics problems. And solving problems, in math or physics, is a skill.
That's what makes math and physics courses different from everything else, and what gives them their reputation for being so much more difficult. You're requiring people to learn a skill when most of them have no talent for it. If you made saxophone a requirement, physics majors would hate and fear saxophone the way music majors hate and fear physics.
Personally I think we're cramming in too much information at every level of schooling. My wife is a kindergarten teacher and I was shocked at how rigorous it is. The state standards are too packed. I teach 8th grade science and I have almost 50 standards the students are supposed to know. Of course I emphasize the ones I think are most important but the point is they're asked to know sooooo much minutiae they don't have time to step back and look at the big picture. Same with math, the advanced students take geometry in 8th grade. We didn't even have that option when I was in school and I have a hard time believing they have a good grasp of algebra from their 6th and 7th grade exposure. Yes teachers are able to pick and choose the "power standards" to some extent, but at the end of the year those state tests matter so much that we have to cram all that information in somehow.
I'm a believer in standards but they need to be adjusted to allow more in depth learning of core concepts.
I have no experience teaching myself so all I can speak knowledgeably about is how I can effectively learn. For me the key is that after reading about a concept, I must immediately put it to use, either in the lab or in trying to work a problem using the concept. So I would propose that lectures alternate rapidly with brief lab sections or homework sections. Don't have a one-hour lecture; have two 20-minute ones alternating with 20-minute problem-working or lab sessions. Thus the professor could explain the Kronig-Penney model and describe the homework problem to be worked. Students would individually work on the problem in class at their desks for 20 minutes and then optionally turn in their answers. The professor would then discuss his/her solution briefly, then lecture for 15 minutes more about the next topic. Students would work on the next problem, turn in their answers, and then listen to the professor's solution. That would be all until the next class meeting.