Lectures are obsolete.

Hear me out: lectures are obsolete and should be phased in favor of a more active approach to learning.

I’ve been taking lectures for quite a few years now. As the topics have become more advanced, I’ve started to notice diminishing returns with how much I learn during a lecture. I’ve noticed that I have to review almost everything from scratch, using my lecture notes only as a list of topics that were covered during lectures.

Why is it that I don’t get anything from lectures anymore? The most obvious reason is pacing. Most lectures are too fast, and I can’t catch up and get lost. A few are too slow and therefore boring and a waste of time. The second case doesn’t happen too often, so let’s focus on the first one.

When I’m in a lecture, I try to keep up with what the teacher says, mostly by writing things down. I try to see that everything makes sense and that the pieces of the math puzzle fit together. Often, I have a little problem that requires a bit of time, so I have three choices:

  1. Ignore the problem and keep up with the lecture.
  2. Try to figure it out and possibly fall behind.
  3. Interrupt the lecture to ask a question and risk public humiliation.

If I ignore the problem, then I start losing grasp of the lecture, and new things become harder to digest. If I try to figure it out, I may fall behind, and new things become harder to digest. And most of the times these are tiny little problems that require just two or three minutes of thought, so I don’t dare interrupt the lecture. This last point is important, and I’ll come back to it.

The result is that I lose grasp of the lecture, and by the end of it I’m tired, hungry, and if I’m lucky I remember just the simplest parts of what was taught. When I go home and try to solve exercises I realize that I have a lot of gaps in my understanding, so I sit down and review. Now my memories of the lecture are useless, my notes get worse as the lecture progresses, so I fall back to the standard (and non-standard) literature. Then it’s almost as if I had never gone to the lecture. In fact, huh, some of these books explain things better than the lectures did. Some of these books have more examples, more solved problems! In fact, this teacher wrote his lecture notes, and his lectures say basically exactly the same as the notes!

So if the books explain things better and I have to review everything again anyway…

…what is the point of going to lectures?

The best lectures I’ve had were ones with small class sizes, where I felt comfortable asking questions and felt like I was adding to a discussion. These were lectures where I felt more like a peer than a pupil, where I felt that there were no barriers between me and the teacher.

That is it. The point of going to lectures is the interaction with the teacher. Talking to a human being who has been there and can try to figure out what your problems are. Getting feedback.

The problem is that old-fashioned lectures don’t incite interactions between the teacher and the students. Even worse, most inhibit them. I’ve had lectures with teachers shutting down students’ questions or answering vaguely (“oh well it’s trivial, isn’t it”). I’ve had lectures where the teacher is giving their back to the class, writing on the blackboard, talking towards the blackboard. In a few of these, the poor souls that dared raise their hands to ask a question had to lower them a few minutes later because they were never noticed.

In general, lectures are just uninviting towards discussions. They are reduced to tepid readings of books or lecture notes. Interactions with students are mostly small questions, a huge chunk of which are of the “there should be a two there, right?” type. Students don’t dare ask the big “I don’t understand” questions because they don’t want to risk feeling stupid in front of their peers.

If there is no interaction between teacher and students, and if the topics of the lectures are readily available somewhere else, then there is almost no point in attending lectures. In most cases, watching a video of a lecture is just as good as attending one. In fact, it is arguably better because with a video you can go back and forward as you please.

Part of this problem can be solved if students read the material of the lecture beforehand. They will have fewer of the smaller questions, and the larger ones that arise will probably be more important and more likely to start a discussion. If students get acquainted with the topic, they will have more confidence during the lecture, and so they will be more likely to interact with the teacher and the rest of the class.

However, in our traditional model, there is little pretense that students will do any reading at all beforehand. Students expect to be taught everything during the lectures, and teachers essentially conform to that expectation. Since most students (including yours truly) won’t do anything other than what they have to do, there is no incentive for them to prepare anything.

Teachers should actively seek that their students interact with the class, instead of being book-readers that hope that students ask questions. The teaching method should guarantee (not just permit) that students interact with the teacher and each other too. The classroom should be a place of discussion, not of real-time copying of notes from the teacher’s papers to the blackboard to the students’ notebooks. Students learn by doing, not just by listening. Lectures don’t let students do.

We’ve just started the third decade of the 21st century. It is time to let the 19th-century style lecture die. There are many different modern approaches to teaching that actually take into account the way humans learn. We can do better than this.