Besides geology, I am also finding that I'm learning a lot about my own learning style this time around. I've found that to feel comfortable with the subject matter, I have been asking myself (and quite often my professors) questions related to the subject at hand, but not necessarily related to the required material for the course.
I think this started because I realized, if I do someday succeed at becoming a science teacher, unless I teach the same exact courses that I'm taking now, I'll need to understand molecules, igneous rocks, plate tectonics, or whatever on their own, and not just how they fit in with one particular course's narrative. I want to cover all the bases, "build a fence around" the material, so to speak.
Then I realized that I was asking extra questions really to feel confident in my own knowledge of the material. I'd like to know, for example, not just that magma plutons form, or even how, but also WHY. On the one hand, I am giving myself more work, digging deeper like this, but on the other, this way it's less about memorizing the shapes and names of random, otherwise unrelated things, and more about thinking through the systems and processes we're talking about. I have found that for me, a subject is actually easier to recall given a foundation of knowledge beneath it.