CUNY has suspended all on-campus classes for the semester. The big question on everybody’s mind is: So how are we going to do exams?

Let me start with a basic assumption: Unless you are physically present, it is effectively impossible to prevent students from using disallowed resources on an exam. I don’t care what online activity monitoring software you want to use, students who want to cheat will cheat.

So what can be done? Some suggestions include having students do their work in front of a webcam, which might work as long as they don’t have “technical difficulties” (and let’s face it, we’ve all been on a videoconference where someone’s screen froze). And if a student accidentally knocks their camera over a and doesn’t fix it immediately, are we going to assume they’re cheating?

Thinking this over, it occurred to me that we’re trying to solve the wrong problem: trying to prevent students from cheating on an exam is not the problem we should be solving. Rather, the problem is making sure our exams reflect student understanding. If the exams are structured so they reflect student understanding, then it is (by definition) impossible to cheat.

There’s an old saying in math (and, I’m sure, many other disciplines): the best way to learn the subject is to teach it. To that end, here’s one possibility. Imagine that part of the assessment is having the student create a short video where they solve the problem while explaining every step they take.

Why does this work? I don’t know; I haven’t tried it. But why do I think it will work? There are many places on the web you can type in a question like “What is the derivative of f(x) = x^3 sin (ln x)”, and a handy little CAS (computer algebra system) will spit out the answer. In some cases, you can pay for a step-by-step solution. If the exam has a question like “What is the derivative of f(x) = x^3 sin(ln x)”, it’s easy enough for a student to cut-and-paste the solution.

But now make them explain the steps of the solution. At this point, the student who has cut-and-pasted the answer won’t be able to do much more than say “That’s the rule that you follow to get the next step.” If they can’t provide an explanation of how they got from A to B, it’s a safe bet they don’t know what they’re doing.

Will this work? I don’t know. But at this point, anything is better than nothing…