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In today's podcast, Ilona talks with Tim Stelzer, a theoretical particle physicist and a research Associate Professor of Physics at the University of Illinois. Over the past few years, Tim has created and used a new system of media tools that have improved learning in introductory physics, by expanding the use interactive web tutorials. His success in creating interactive tools predated these tutorials, as is also one of the inventors of the I-clicker™ student response system. Tim is also a regular on the University of Illinois "Incomplete List of Teachers Ranked as Excellent by Their Students." Listen to this podcast to learn about how Tim expands physics beyond the textbook and the lecture formats, and how he has measured significant increases in long term learning and positive attitudes toward physics among his students. [12:15]
Full transcript
ILONA MIKO: Welcome to the latest edition of NatureEdCast. I’m Ilona Miko and today we’re talking to Tim Stelzer, a theoretical particle physicist and a research associate professor at the University of Illinois. Over the past few years, Tim has created and used a new system of learning tools that have improved learning in introductory physics by expanding the use of interactive web media. He was one of the inventors of the I-clicker student response system and is a regular on the University of Illinois “Incomplete List of Teachers Ranked as Excellent by Their Students.” Welcome, Tim.
TIM STELZER: Thank you!
MIKO: Thanks for joining us! So, you’ve created an interesting approach to physics learning to prepare students for their lectures. Why did you think there was a need to change the way that students prepare for the physics lecture?
STELZER: Well, I think all faculty really value the time they have with the students and in my case that is, in fact, the lecture and so it was really concerning to me when evidence starting coming in that what I’ll call the traditional form of lecture — the idea where we provide content to the students during that 50 minutes — was pretty ineffective for the students and in fact I even had some of my own data where I asked the students how important was the lecture in helping them learn the material and was really disappointed to find out that less than half of them, only 40% of my students, said the lecture was important for helping them learn the material. So, I was interested in making a change to that and one of the ideas that was going around at the time was the idea of pure instruction. And that was instead of spending the time providing content to students, I would provide some content, but most of the time would be spent with the students trying to apply that content to different problems, discuss the issues with each other, and then report back what they thought the solution was. Well, this idea seemed to work very, very well in the classroom. In fact, that motivated us to develop the I-clicker student response system. We quickly learned, though, to take full advantage of this we really needed to know where the students’ strengths were and where their weaknesses were so we could ask good questions. And once again we looked at what other people were doing and adopted this idea called “Just-in-Time Teaching,” where we’d ask the students to fill out the survey before lecture, and based on their responses to that, we would tailor the lecture and tailor the questions. And so, this again was a great idea. The difficult part of it was what we found out was students really didn’t have much content — they weren’t learning from the textbook. And so that was a real challenge for us in terms of wanting to be able to spend time not providing content to the students, but having them discuss it. So, we needed some mechanism to get them better prepared so we could take better advantage of our lecture time.
MIKO: So, how were you able to apply these ideas about preparation to actual physics instruction?
STELZER: Yes, so what we did is we looked around at some research that had been done on how people learn, and there’s a whole field, it turns out, about multimedia learning. And it seems that people are very well designed to learn when they have both an audio and video input of the data. And of course with the advances in web technology, it seemed like a perfect match. So, what we decided to do was to develop what we call pre-lectures. They’re multimedia content that we can put online, they’re relatively short (about 15 minutes), and the students can view these before coming to lecture and it really prepares them. It provides them the base content that they need to be able to get the most out of lecture.
MIKO: So, with these pre-lectures, I understand you actually did some formal studies. You studied how effective they were and you conducted two main longitudinal studies following students: one outside the classroom in kind of a what you call a clinical setting and one inside the classroom. Can you tell us a little bit about your comparisons and what you found with these studies?
STELZER: That’s exactly right. So, preparing these pre-lectures is an enormous amount of work, so we wanted to make sure that what we’re creating was in fact effective. So, the first study that you mentioned is a clinical study, and what we did there is we invited some physics students to come in and participate and we paid them some money and they actually came into the physics department and we divided them into two groups. One group of the students was given some material to read from a standard textbook. The other group was given a pre-lecture on the same content. Then they could spend as much time as they wanted studying that or doing the activities and then immediately afterwards we gave them a test on the material that they had seen. And so we got one result there and then actually we invited them to come back a couple weeks later and just take another test, to see how well they remembered the material. And so in that clinical study we had very nice results. The students who saw the pre-lectures actually scored about 10% to 13% higher on the exam, both immediately afterwards and a week later when they came back to do that. So that was quite encouraging. And since it seemed to work we decided to go for it and do the whole semester’s worth of material. And we did that and applied it in the classroom and the results were again very exciting because just going to lecture was a really different experience. The students were answering the pre-lecture surveys much better; they were asking much better questions in class and it all felt really good. So we were very excited when the first exam came around — to see if we would once again see these dramatic improvements on their exam performance — and in this case it was: They did better, but they didn’t do the 10 to 13% better that they had done in the clinical study. So, a little disappointed in that perhaps, but it became clear what was happening and why they didn’t score as much higher as we thought. It was basically the students were taking other classes and so they found the physics easier to learn and so they were actually spending more time on some of their other classes.
MIKO: So basically you gave a gift to some other professors with that one.
STELZER: Yes, I guess so, that was a little bit unintentional but it was—
MIKO: —It’s a good benefit all the same. I’m curious, could you describe the pre-lectures a little bit, just for a moment here, and give us a sense of what the experience is like for a student involved in the multimedia pre-lecture?
STELZER: Oh excellent. Yes, I should have described that before. What happens is the student, it’s about a 15 minute experience and it’s divided up into about two minute segments and we call them slides or scenes and the student will watch one and view the animation and listen to the audio, and then they can click on to a next slide and interspersed in there, there are some questions that the students can answer to basically help them see if they’re understanding the material at the appropriate level.
MIKO: So it’s assessing them as they go through concept learning that’s reinforced by both visual and audio experiences.
STELZER: Exactly.
MIKO: OK. And it takes about 15 minutes. So, I’m curious, so you’ve quantified how effective these have been for performance. It sounds like a whole letter grade is probably some of the improvements you’ve been seeing, if the average is about 10 to 13% improvement, which is really important — it’s very significant improvement in their understanding. I mean both for their performance and their comprehension, but also their grades are better, which means a lot to the students, I’m sure. But I’m curious if you could talk a little bit more about, is it really enough to say that the students perform better? Do you have any other findings you could tell us about that helped inform your teaching or indicated something you were doing was working to the benefit of really effective teaching?
STELZER: Yes, absolutely. As I mentioned, when we looked at the exam performance for the hour exams, it wasn’t the full 10% higher that we were expecting. It was a little bit less than that and so we wanted to have another measure of the impact this was having because qualitatively it really felt much, much better in lecture. And so one thing that we happened to have is these surveys we had done with the students. I started this by mentioning how disappointed I was that the students were — only 40% of the students were saying the lecture was really important in helping them learn the material. There were a couple other questions on that survey that caused concern for us. One was that in fact only that 80% of the students considered this physics course to be one of the hardest courses on campus and only 40% of the students, at the end of the course, had a positive attitude towards physics. So, again, we asked those same questions again after implementing these pre-lectures and here the changes were pretty remarkable. First, what used to be 80% of the students saying it was one of the most difficult courses on campus, that number dropped to only 40% saying it was one of the most difficult courses on campus.
MIKO: That’s fabulous. That’s really great.
STELZER: Yeah, it’s really nice and it’s not that we necessarily want our course to be so easy, but you worry when you’re at the 80% level, you’re really pushing the students a little bit too close to the edge. Some other nice information was their attitude toward physics at the end of the course. Remember, I said before this only 40% had a positive attitude towards physics at the end of the semester and after implementing this change 80% of the students had a positive attitude. So, that’s really, really nice for us to feel that they're understanding the material and they’re feeling better about it.
MIKO: Yeah, so in general, amongst all of their other courses in comparison, they were feeling like this was a more fun experience for them and in the classroom as well, during your lecture.
STELZER: Yes, and then my favorite one of all, the thing that motivated this in the beginning, was how important was the lecture to helping understand the material. Remember only 40% of the students were saying that the lecture was important in helping them learn the material. After making this change, 80% of the students said that the lecture was really valuable in helping them understand the material. So, this difference, getting them to come to lecture with the content, with the content or some content already at their fingertips, really made a difference in what they were able to learn while they were in the lecture spending the time with us. So, that—
MIKO: It definitely makes it more rewarding for the lecturer as well, I would think, to hear that the students found the lecture valuable!
STELZER: Absolutely, absolutely. I really appreciate the time I have with the students and you want to use the time as effectively as possible, and we feel like this change in the pre-lectures to get them ready for lecture and what we’re able to do in the classroom has really had a big impact.
MIKO: Well, thanks for telling us about this today, Tim. These pre-lectures are really interesting, it’s actually a nice quantified result of how you can effectively use multimedia to make in class learning better and I think that’s great. The future seems to be a hybrid of the two; improving both and having one complement the other. It sounds like you’re doing a great job of that. Thanks for joining us today!
STELZER: Thank you so much.
MIKO: Thank you for listening to this edition of NatureEdCast. You can find this podcast and others at nature.com/scitable. That's nature.com/s-c-i-t-a-b-l-e. Please join us again next time.
