With lectures, you only get out of them what you're willing to put in. You might be bored by the slides, but that information is still important. If you spend that time thinking from the teacher's perspective, you might get a better grasp of the material.
Photo by John Keane.
Taking good notes is one of the best things you can do when it comes to lectures, but sometimes there's so much content it's practically impossible to capture it all. Even worse is when you know you can access the lecture slides later on, practically giving your mind the go-ahead to wonder.
Instead of letting yourself succumb to boredom, Stephen Boisvert at Quora suggests you spend that time thinking from the teacher's perspective. As you feel the lecture lose its grasp on you, stop scribbling mindless notes, just pay attention to what's being covered, and start to think about the questions you would ask others on an exam if you were teaching this lesson. Then, in your notes, try to answer them as best you can. If you can't answer something, make a note to look it up later, or ask the teacher about it after class. It may not make the subject matter more interesting, but it will engage your brain more and give you a real chance to absorb some of the information.