After students watch an online lecture, what do they know? What do they think they know? How do you know what they know?

Instructors just venturing into online learning often have the valid concern that they might not be able to tell if their students are “getting it.” Without being able to see students during the lecture, they won’t see the encouraging nods, the confused raised eyebrows, the glazed-over look of boredom. And when your students have so many potential distractions available on the Internet just a click away, it can be troubling to not know how much of their attention you have when they’re watching your lecture.

And those instructors are right. You won’t know if students are getting it during your lecture. But I would suggest that reading body language is a pretty imperfect way of measuring student comprehension in the class anyway. Are you able to make an accurate assessment of every student in your class in this way? Or are you just focusing your attention on the eager students in the front row? How do you know students aren’t feigning understanding because they don’t want to be embarrassed after you’ve already explained something twice?

In any case, the issue is certainly exacerbated in online classes. And new online instructors frequently ask how we can address this. I think they expect me to describe some fantastic new technology, perhaps eye-tracking hardware that can make sure students are watching the lecture, measuring their pupil dilation and using an AI algorithm to determine if they’re learning anything or not.

The real answer is much more basic: ask students to demonstrate their learning. That’s right—more assessment.

Instructors sometimes resist putting more knowledge checks into their courses. They might think that it suggests their academic discipline can be reduced to a multiple-choice question, or that it’s something K-12 students need but not college students. But these checks need not (and shouldn’t be) the ultimate assessment for your course. They’re just the beginning of the scaffolding process, making sure students can demonstrate basic recall and application of the core concepts. Not only that, they can serve as a feedback signal to students—letting them know whether they’re missing important points before moving on.

And in the online learning environment, this kind of assessment can be quite low-friction. You could certainly just include a short quiz after the lecture, but Panopto, DePaul’s video hosting platform, has recently added a feature that allows you to insert quiz questions directly into the middle of a video. Students watch a slide or two, answer a question, get instant feedback, and either rewind the video to catch what they missed, or keep moving forward to the next concept. These mini quizzes don’t link to the gradebook, but instructors can view student data and use that to deliver a just-in-time supplemental lecture if there was a concept that seemed to stump students, and review the lecture material to make it clearer for the next cohort.

Are your students really learning from your lectures? Are they hopelessly confused? Did they just push play and then stare at their phone playing Candy Crush Saga without actually paying attention at all? There’s really only one way to find out.