If the course required turning in a notebook, I pretty much had a guaranteed 'A' on all the tests.
For the rest of my courses, it could be hit or miss. The stuff that sticks, sticks for a long time. I always nailed the end of semester final exams. I never put in any effort into memorizing the last few things that would get me a good test score, resulting in some mighty inconsistent performances. I remember my biology class - it was the first class that I managed to hit every passing grade in the same semester. An A on the final, but hit B, C, and D for the 6 week grading periods (I don't remember what order I got the grades in, though).
Shoot, I ran cross country and held down a job. When was I going to find time to study?
I almost never studied in high school. I'd look over my notes a few times before exams. I did do my homework assignments and pay attention and take notes in class, but that's it. I don't even think I ever opened my books other than to find the assigned homework problems in them. I didn't need to study in high school; I had mostly As and a few Bs along the way without studying. I had a very rude awakening when I got to college and actually needed to study and didn't really understand what was involved in it. On the upside, I think my own mistakes have made me a better teacher now, because I can anticipate the trouble my students have, be proactive about it, and help them overcome it faster than I did on my own.
I did just enough to get by. I remember spending some time writing papers but not very much on studying. I was kind of a delinquent and more interested in boys than books. Our high school wasn't that demanding, though. I did the standard four years in three. I even had a waitressing job during the last year.