[no_protocol]

As a student, I attended every class with pen and paper and scribbled tiny illegible notes on almost everything the instructor presented. I rarely referred back to them, but when I did, it was invaluable.

As an instructor, it is painfully obvious how little attention some students have for lecture material. Taking notes at least forces you to continue listening, even if you are just writing them down on autopilot.

Edit: Bonus content. Here's a sample page[0] of notes from the first Computer Science course I took. I knew all of the material already, but still wrote down almost everything presented. Notice how there is very little structure, just filling the page up as densely as possible. This was very typical for me.

[0] http://i.imgur.com/btviZRH.jpg