umm, just a comment, but if you have to study for five hours for one test, what exactly does that show? doesn't that somewhat reflect that not much was learned in class through lecture and by doing hw? if anything, studying should be called review, to refresh your memory on what you already are supposed to know. i think that nowadays, people are doing a lot more of this "all night study" stuff, then take the test; that test now becomes a reflection of how much you can cram into your head in five hours, not exactly what you've learned over the year.
also, it's been shown that the attention span of the average human is roughly 50 minutes. you shouldn't "study" for more than 50 minutes at a time.
i'm glad im done with high school, but man, i tell you, those AP classes really don't prepare you for college level classes as well as you would think. college is different than HS.