In-Class Active Learning Examples

Tadayoshi Kohno (Yoshi Kohno)
6 min readOct 26, 2022

The following notes capture some of my early (to me) thoughts about active learning. I wrote these notes in 2014, in an email to other educators. A recent conversation reminded me of these notes. Although I’ve changed my approach here and there, I still largely agree with many of the ideas in this email. Thus, I’m posting this email here with only minor modifications.

None of these ideas are really my own — they build on the amazing ideas of many other educators. Underpinning all these ideas is the importance of seeing all students as people and active co-participants in a relationship that maximizes their learning opportunities.

End-of-class poll.

I sometimes take a short written poll at the end of class. My questions are generally of the form: (1) what was the clearest part of today’s class and (2) what was the least clear / most confusing part of today’s class. This gives me an opportunity to take a pulse of the class and address gaps at the beginning of the next lecture.


I am also a big fan of think-pair-share and encourage everyone I talk with to at least experiment a little with it. Think-pair-share is an active learning technique designed to help engage all of the students in mentally exploring a topic. As background, I used to say things like: “I’ve now presented a system; can anyone identify some potential security risks?” I’d then wait for someone to raise their hands … very often the same group of people would raise their hands. Another option, which I was never really comfortable with, was calling on random students (which is hard on the students too, because they haven’t had a chance to really think about the question yet and hence are approaching the question cold). Additionally, sometimes, the students who are not called on — or who know that someone else will raise their hands — will disengage during this time (see the graph I link to at the end of this email).

What I sometimes say now: “I would like you all to take 30 seconds to think about this system that I just described, and think about what the risks might be.” Pause. “I would now like you to turn to your neighbor and each share what you came up with.” Pause. “OK, if only one person has been talking in your small group, make sure the other person talks.” Then, after that, I ask if anyone would like to share what their group discussed. If an instructor really wanted to, they could now call on people directly, and this would no longer be cold-calling. However, for me, I prefer not to call on people at random; I feel like it is better for students to volunteer, as I don’t know if there might be reasons why a person may not wish to or may not be able to talk on any given day.

When I first started using this technique, I was shocked at how little time it actually took. And the students became *way* more engaged. And I think all the students started to really internalize the material in ways that they previously hadn’t. (And, sometimes, for large classes in large departments, active learning exercises like this can help students meet new people.)

There are many variants, and I could probably discuss this for hours (or at least minutes). But here are some variants that I also like.


After presenting a complex topic, I try to avoid asking “does everyone understand this?” It’s not clear what an expected answer to that question should be. And sometimes people are uncomfortable saying “no”. So instead I say: I would like you to find a group of two or three people and summarize within your group what I just presented. I’ve found that this really helps students understand the material and become engaged. This also really helps make sure that all the students are on the same page before we start exploring the topic in even more depth. Also, I think I’ve noticed this being helpful for non-native English speakers, e.g., the group of students from country X who start to discuss in their native language.

After the summarizing exercise, I often ask: did any questions come up as you tried to summarize what we just discussed? Was anything unclear?

Come up with questions.

Sometimes students can be afraid to ask questions. But sometimes I KNOW there are questions in the room, but that students just aren’t asking them. So I do this exercise: “I would like you all to take out a piece of paper, and write down three questions about what I just presented. (Or just come up with three questions, even if you don’t write it down.) … Now form groups of two or three and share your questions.” Then I ask groups to share with me some of their questions.

This process can help students feel much more comfortable asking questions that they might have previously thought of as “dumb”. I think that it’s easy to see why. For example, suppose two people both have the same question, but both think it’s not a good question and are afraid to ask their question in class … after they start talking with each other, they realize that they share the question and it is in fact not a bad question. This process can also serve to bootstrap a deeper discussion of the topic because the students do ask really interesting questions!

Worksheets with gaps.

I LOVE worksheets with gaps! Worksheets with gaps give students the opportunity to explore a concept themselves, IN class, get active feedback from their peers, and identify gaps in their knowledge. I am attaching an example of a worksheet with gaps, which I used in CSE 484. Q1 is a question I asked students to work on _before_ summarizing the stack layout on x86 — this question gave the students an opportunity to refresh their own memories from previous courses, and identify gaps in their knowledge _before_ I presented the material (so that they knew which parts to focus on). For Q2 and Q3, rather than just presenting the attacks in the lecture, I had the students work in pairs to try to identify the attacks themselves. If the students were able to figure out the attacks on their own, they learned a lot (I think). And if they weren’t able to figure it out on their own, they paid extra attention to my presentation of the attacks, and I think also learned a lot. [The worksheet with gaps is here.]

Active learning.

As the above probably makes clear, I am a big proponent of active learning. The following figure captures my understanding of attention in a traditional lecture-only lecture (caveat: I hand-drew this image; I do not know the original data sources/studies that informed the creation of these types of images, but one can find similar images through web searches).

This image captures the general idea: Shortly after the start of a lecture (after people are seated and settled), there is generally high attention to the lecture material. Toward the end of the lecture, people might return their attention to the lecture (if their attention during the lecture went to other topics). Emphasis on “general idea” because this is a hand-drawn curve and not a curve resulting from empirical data.
The small text at the bottom of the figure reads: This image captures the general idea: Shortly after the start of a lecture (after people are seated and settled), there is generally high attention to the lecture material. Toward the end of the lecture, people might return their attention to the lecture (if their attention during the lecture went to other topics). Emphasis on “general idea” because this is a hand-drawn curve and not a curve resulting from empirical data.

Essentially, this figure shows a graph of “attention to the instructor” as a function of time in a traditional lecture-only lecture. Note that it starts moderately low (while people get settled, put their phones away, stop conversations, stop thinking about the bus ride over, etc), increases a little, and then decreases until the end of lecture, where it picks up a bit. Active learning, at least as I understand it, is designed to interrupt this process and get people re-engaged.

Start of class surveys.

I sometimes start class with a short question: please take out a piece of paper and write down two of the most important concepts from the LAST lecture. This helps bring people back into the context of the course, and I think (without proof) helps reinforce the memory of the previous lecture. I ask students to do this individually, or in small groups, to make sure that everyone actually tries to think about this question. One of my conjectures (again without proof) is that this can also help students pay attention to the meat of the current lecture once it starts (see the discussion of the figure above).



Tadayoshi Kohno (Yoshi Kohno)

Tadayoshi (Yoshi) Kohno is a professor in the UW Paul G. Allen School of Computer Science & Engineering. His homepage: