Generating buy-in is an ongoing process

I had a great moment in my calculus-based introductory E&M course today. I had spent the last few minutes explaining with great enthusiasm and great clarity (according to all the nodding I was seeing) how the electric field due to an infinite sheet of charge does not depend on the distance from the sheet of charge. I pointed out the progression of the 1/r2 dependence for the point charge, the 1/r1 dependence for an infinite line of charge, and the 1/r0 = constant dependence for an infinite sheet of charge. I argued that you could easily see that it was constant because the electric field lines have a constant density (neither converge nor diverge) no matter how far you get away from the sheet of charge.

Then I asked them the following clicker question…

Clicker question from Knight – Physics for Scientists and Engineers

…and 2/3rds of them incorrectly chose option D which says that the electric field due to this sheet of charge changes with distance from the sheet.

And I was delighted! This created a great moment to generate some more buy-in for the methods I use in the course.

I will roughly paraphrase what I said to them. I’m pretty certain it was more enthusiastic and less coherent when I was saying it in class:

Before this clicker question, you all sat there nodding in agreement with me as I explained this idea to you. And then when I turned around and asked you to apply the concept on a fairly straight-forward question, 2/3rds of you did not answer the question correctly. This right here highlights exactly why I run this course in such an interactive way. Until you have had to wrestle with the concept and make the understanding your own, you can easily fool yourself into thinking that you have learned the idea.

Today was a great day.

Why I use clickers in small courses

In the comments of my post discussing my doing away with clicker participation points, gasstationwithoutpumps commented:

I understand clickers for large lectures, but I’ve never gotten the point of them in a class of 10. Could you explain why you feel them useful in a class small enough that you can see all the students’ faces and ask them questions personally?

He provided me with a great opportunity to step back and consider my own personal reasons. Here they are. Please keep in mind that I am not trying to convince anybody that these are THE reasons to use clickers in a small classroom or to not use them, but are simply my reasons.

With clickers I feel that I can engage every student

I’m going to quote Stephanie Chasteen (sciencegeekgirl) from one of her posts in her series on clickers in upper-division physics. This is her response to a common argument against using clicker in upper-division courses:

Discussion is easy in small classes, we don’t need clickers. Some instructors do use other methods, such as colored cards, in small classes. The technology itself may not be as crucial, but the teaching method (of asking a question and encouraging students to discuss it with their neighbors) is still incredibly powerful. Plus, students can still “hide” in a class of 10. Or even a class of five. And so can their misconceptions. Students may think that they are following, but until they have to answer a challenging question, they may not be aware of difficulties that they have.

Despite the fact that I can ask all of them questions personally, when I ask one student a question I present the rest of the students the opportunity to “hide”. Just like in larger courses (well larger relative to 10), I want every single student to actually commit to an answer and become vested in the income. Without getting them to commit to an answer I feel that they often won’t fully consider what I am asking them. My analogy is that it is like the difference between having a character with an unfamiliar name in a book and just sort of mentally mumbling it every time you read it, compared to reading it out loud and having to actually commit to how you think that name might be pronounced. Committing to the specific answer with the clicker is like asking a person to try to pronounce that unfamiliar name, they can’t just mentally smudge it anymore. Without the clickers or some low-tech variation, I might be able to engage a few of the students in trying to pronounce the name out loud, and a few others might honestly try to do it without being called on. But like Stephanie says, students can still “hide in a class of 10.

Clickers help me create a safer learning environment for my students

Even in a class of 10, I find that there are usually some students that often do not feel comfortable discussing their understanding with the entire class. The clickers facilitate the argumentation process for these students in a smaller-group situation in which these students feel more comfortable, but are still help accountable for their answers. They help establish a culture where on most questions each student is going to be discussing their understanding with their peers. Clickers are not the only way to accomplish this, but are the way I do it.

Clickers are a very familiar pedagogical technique for me

I would say that my use of clickers falls much more in the “question driven instruction” camp then the “testing for understanding camp” (Ian Beatty talked about this in his AAPT 2011 Summer Meeting talk). And this has become a very familiar way to run a course for me. I am comfortable setting students up to learn the challenging application of a concept or to figure out how to proceed in a derivation through the use of clickers and group work on whiteboards.

Clickers allow me to record student understanding

As both a physics education researcher and somebody that continuously strives to improve my courses, the ability of the clickers to record snapshots of student understanding is invaluable.

So long clicker participation points

I use clickers in all my “lecture”-based courses, with enrollments in these courses ranging from 10-36. I have offered participation marks to students for answering at least a certain percentage of the clicker questions in a given class. At first I was giving out 5% of their total mark, then 2%, and now it looks like I’m doing away with those marks completely.

I have never really liked the idea of giving marks for attendance (even though that is basically what I was doing). I was following the common advice that I had encountered from places such as CWSEI’s Clicker Resource Guide and other folks who have used clickers a lot. And it seemed reasonable to me. My classes are very interactive and there are students that might otherwise try to zone out or not show up, and I always try my best to help the bottom quartile succeed. But this sort of practice raises all sort of issues with external motivators. Of course I give tons of marks to students for doing their pre-class reading/screencast viewing assignments so I am not above giving participation marks to students for doing things which I think will help them learn.

When giving clicker participation marks I have always allowed students 3-4 free days that they can miss or not participate, and not be penalized. But I always end up with a few students that want exceptions above and beyond these free days. Doing away with the clicker participation points also does away with this hassle.

The last thing that it accomplishes is that I hope it will reduce guessing on clicker questions. With the clicker questions not being worth any marks, I can ask students not to randomly guess and only answer a question if they have some reason to believe the answer they are choosing. Back in January Peter Newbury talked about how, due to student guessing, you can overestimate how many people actually got a given clicker question correct. Without the participation points, students can feel that they won’t be penalized for not answering a question, which I hope will reduce the guessing effect. Of course another way to get at the guessing effect is to, every so often, ask them a clicker question about how confident they were in their answer, and to have “Randomly guessed” be one of the options.

I have enough data to know what sort of participation level to expect in my own courses with the clicker participation marks being dangled in front of the students. So I will be able to compare the participation level between using clicker participation marks and not after the fact. Of course these numbers will be convoluted with my slowly improving ability to generate student buy-in, but I will at worst be able to tell if participation went down.

So long clicker participation points, I hope I never feel the need to use you again.