The problem is worse than I thought.

Thanks for posting that Quirt.

This semester was the first time ever that I included a cell phone policy in a syllabus. The policy is basically no phones on desks or otherwise visible. I included it because it's a big class (compared to my other classes) and a 2000-level (200-level) unlike the 3000/4000 level courses I usually teach.

Anyway, I pointed out the policy at the beginning of the semester, but decided (without tell students this) that I would not actively police them. So far, there's only one student who doesn't follow my policy (this student is also currently getting a D).

But generally students aren't on their phones in my classes. I think that's because the classes are small and I teach mostly majors. And my classes move fast, I think students know they can't afford not to pay attention.

Next semester, I'll teach a class in English (I usually teach in Japanese) and it will have students from a wider variety of majors in it. I think I'll add the no-phones policy again. But maybe I'll also do so with a little more discussion first...