Recently a friend of mine sent an email to a list I'm on, asking for advice for teaching a 200-student class in some kind of non-boring way. In particular, she asked about clickers, and since I've used them before, I wrote some words back (at like 6am in Germany because of jet lag; I'm here for ICME). I decided to edit those words into this blog post for more people to read.

A few years back, I taught a 200-ish person calculus for life sciences class (Math 121/122 at SDSU). I used peer instruction with clickers and it was great; there's no other way I could have gotten the level of engagement I wanted out of a class of this size. I've also done a fair amount of training / support for instructors who want to try peer instruction with clickers for the first time.

NB I'm saying “peer instruction with clickers;” think about this phrase like one of those big German compound nouns that are all mashed together. Maybe I'll abbreviate this as “PIwC.” Clickers are just a platform, and you have to have a pedagogy in mind to run on said platform. (In particular, if you're just going to use clickers as a way to ensure attendance, students will chafe.)

In case you haven't heard of it before, peer instruction (PI) is a clicker-based pedagogy invented by Eric Mazur, a Harvard physicist. The idea is that your clicker questions are mostly conceptual (Mazur calls them ConcepTests), and you run them in a four-step process:

  • first an individual vote, which makes students commit to one particular answer (an important metacognitive skill),
  • then some time for small-group discussion with your neighbors during which you're supposed to come to a consensus, which makes students verbalize, listen to, and critique each others' reasoning (an important metacognitive skill),
  • then a second group vote,where you're supposed to vote the same as your neighbors,
  • and then some whole-class discussion, where you can again make your students exercise their verbalizing, listening, and critiquing skills.

NB that one of the big upsides of this process is the practice and (hopefully) development of metacognitive skills. This is something that I think a lot of classroom practices aren't particularly strong in, which makes PIwC a valuable addition to your toolbox.

Within this broad framework, there's room for a lot of interesting variation. This is another thing I really like about PIwC - even though it looks pretty rigid, there's lots of room for you to tweak what you're doing on a per-course, per-class, or even per-question basis in service of whatever your particular aims are. Here's some of my favorite tweaks:

  • Most clicker software will display a histogram of student responses, and you can choose to show students the histogram after the first vote or wait until after the second. Most often, I show the histogram right after the first vote. I do think you should show the histogram at some point, for student self-evaluation purposes. (Oh look, more metacognitive skills.)
  • There's lots of fun questions you can ask to provoke debate (and more metacognition :) ) in students' groups:
    • “Ooh, interesting, big split between A and C, why do you think that is?”
    • “Seems like everyone is pretty convinced B and D are both wrong; how do you know?”
    • “Why might a reasonable person think the answer is B?” (NB that there are probably good reasons for B, given that you carefully chose this question to have reasonable distractors.)
    • “What would the question have to be in order for the answer to be D?”
    • “How can we decide between A and C?”
    • “Remember that we just decided that X is true; what would that mean for this question?”
  • It's often worthwhile to have a little whole-class discussion before the re-vote.
  • Wander around the room during the group discussion and try to overhear interesting things, then ask if you can pick on them for the whole class discussion.
    • “Alice said something interesting to her group that I asked her to share. Go ahead, Alice.”
  • I told you above that the questions are usually conceptually-focused. Maybe use some moderately procedural questions, but I'd lean away from anything that's just number-crunching. There's a happy middle ground of questions in which conceptual misapprehensions will reveal themselves in procedural mistakes; I'm sure you can think of many of these in whatever class you're teaching.
  • I've even done a thing where the right answer was not given as an option in the original vote, to provoke some productive (and amusing) frustration. :)

It's also worth noting that there are probably, floating around on the internets, good banks of ConcepTests for whatever your class is. Also check your textbook; many publishers provide ConcepTests or something like them in their online supplemental materials. So this is nice because you don't have to start from scratch, and even if you don't like the questions you find, you can use them as templates or inspirations for developing your own.

Of course you will have people who will disengage during the discussion process, or who will have off-topic conversations with their friends. Wandering the room will control this to some extent, but there's just nothing you can really do to ensure that all 200 students are on task all the time. It's the real drawback of large lecture classes. Womp womp. Don't pull out your hair trying to control this behavior; it's not really worth it. Whatever minimal gains you make in terms of time-on-task will generally, in my opinion, be canceled out by equivalent gains in student grumpiness. It's an easy way for you to be perceived as autocratic and heavy-handed, and that carries a real danger of damaging your classroom community.

So those are some tips that I think will help you get started. Please feel free to ask any other questions you might have, and I'll do my best to answer them.