Everything I Say Might Be Important

The other day, while working intensely on editing a document in a cafe, my attention wandered for just a moment (or two) and I tuned into a nearby conversation between two undergrads. One of them said something like this:
I hate Professor X. He never tells us whether anything he says is important, so we have to assume it is all important and so I need to take notes on everything he says and it is impossible to do that.
There was a bit more to the conversation, and it seems that this student is really struggling to sort out what is important and what is not important in a lecture, and therefore isn't getting much out of the class. If a lot of information is presented in each class, and all of it is theoretically equally "important", she can't possibly take it all in, she spends a lot of time feeling frustrated, and she therefore hates the class (and its professor).

One thing that interested me was the idea that it's better to assume that everything might be important than that none of it is (or might be). A famous gripe of professors is when students who miss a class or arrive late ask the professor if they (the students) "missed anything important". Would you rather have students wonder if you happened to touch on anything important in a particular class, or would you rather have students assume that you are probably saying lots of important things (if only they knew what they were) and hate your class as a result?

Not knowing anything about the professor or class or student in question, I am not going to speculate more about that particular situation, except to say that I hope that the student goes to talk to the professor -- not to complain, of course, but to discuss strategies for understanding the lecture material and thereby to alert the professor that at least one student is confused and struggling.

Overhearing this conversation made me think about how/whether I convey **What Is Important** and What Is Not, while teaching in a classroom.

Most of us are well aware that some students classify information as important (likely to be on the test) vs. not important (safely ignored). And many of us professors think that everything we say is in fact important (and could be on the test), but realistically, some of our pearls of wisdom are more pearly than others. We may emphasize a certain topic (perhaps even specifically described as important, key, critical, significant, fundamental etc.), and then some/most of what immediately follows is elaboration: we give examples, we try to explain and not just state. All of that is important, but there is also sort of a hierarchy.

I am going to try to be more aware of this in my classes, but I am curious as to how often I say "This is a really important point/concept/question" (and then, ideally, explain why it is important and not just assert it). I think I try to be clear about this and not just assume that students will automatically know, but to be sure, I do provide review questions that represent important information from each class. Or, I should say, the most important information because, of course, it is all important.