Interactive Lectures: Roger TobinPhil Gay
This div will be replaced by the JW Player.
Every day in a large class I will use a method called peer instruction which involves stopping several times during the class and posing to the entire class a question like this one. And it turns out that students have a great deal of difficulty with this question. And the reason they have difficulty is because of a very common misunderstanding of how batteries behave and
of the difference between current and voltage in an electrical circuit. So they discuss it and they vote on it and most of them get it wrong. And one of the beauties of it is that then you can do the demonstrations. So you set this up. Have your two bulbs. They light up. So if put a wire across the second bulb, what happens to the first bulb? Do you think it will stay the same?
You think it will stay the same. That’s actually the most common guess. So in fact, the other bulb gets much brighter, the bulb you put it across goes out and the other one gets much brighter.
One of the things I’ve learned is that demonstrations don’t work unless you get the students to commit to an answer ahead of time. One of the things I notice just in the classroom is after I’ve asked this question and they’ve voted when I stand up with the board, I have everyone’s attention. They want to know, they want to see.
And there is a gasp in the room when they see what the answer is. And the people who got it wrong groan and the people who it right cheer and, you know, it’s a level of engagement with the material that you just don’t see if you just stand up there and do it. Recently I’ve been doing that using a technological system called ‘clickers’ which are little handheld devices
that the student have that they can use to do the voting. That’s not an essential part of the pedagogy, but it makes things a little useful. One of the questions I ask is ‘So, should I keep doing this? Should I keep using this system in the future?’ And, so over here is the data for the people who were strongly in favor, and in favor, people who had no opinion,
people who said I shouldn’t, and people who said I really shouldn’t. And over 90%, 93/ 94% say ‘Yes, you should keep doing this.’ Another thing I asked is about these in-class questions, these questions I ask and have them vote on, the homework, the recitation sessions where they meet in smaller classes to go over homework,
the textbook, and the labs, and by the way this was a class back in 2000 when I was not using clickers, the absolute highest thing in the whole lists is the in-class questions. So, one thing I have very clear evidence for is that the students like it.