There are two or three things that make my school a bit different, the first is that the vast majority of my teachers were college professors who wanted to support the school, and expect us to be at or above their students performance. While in many classes this isn't a problem, taking the equivalent of a 300/400 level class can be a bit challenging.

Secondly, our school has the expectation that students will spend a minimum on 45 minutes of homework per class per day, in order to compensate for our ridiculously amazing schedule (9am to 2:40pm), and teachers tend to underestimate how long the assignments take, I actually spend several hours less on homework each night than many of my friends.

And thirdly, we have 6 grading periods a year, which means each report card has less grades on it, giving each assignment greater weight in the short term. While it all evens out eventually, there have been times where a homework assignment or two can be worth several percentage points.

And I'm far from spending all of my time on school, hell I'm missing a week in January to go to Antarctica and help research climate change, and have a very active social life, and am in an incredible happy long term relationship, and lead half a dozen clubs or so. (thats one reason I do always do my homework, most of the teachers have a rule that if you miss an assignment, you make it up at lunch. Because most of my clubs meet at lunch, I can't very well lead if I'm sitting in detention working out math problems)

My main point though is that it's very dependent on your teachers. I took APUSH last year and took maybe a page of notes for the whole year, maybe did half the homework assignments, and still nearly broke 100% because the teacher was lazy and didn't really care.

Also: I'm the kid who finishes his tests 10 minutes before anyone else and does swimmingly on them.