What I've learned so far (still in highschool) from school is:
Teachers (most of the time) are working for your best interest. Teachers usually don't always want you to end up failing, no matter how strict, of course this doesn't apply to all teachers.
Although I don't always do it, sitting in the front is the best way to learn.
Starting your work as soon as you get home is so much easier than starting it at 11 P.M, after you're done with Basketball and playing your video games.
Taking notes without actually understanding what you're writing, is (to me) counterproductive, I could sit through a class for an hour and a half taking notes, and I won't have any idea of what just happened.
Working with people who actually get there work done, instead of friends, is sometimes the better choice.
Slacking will catch up to you
Being organized is the best feeling ever when you're looking for your homework
Although I'm still in high school, these are just some things I've picked up throughout my years. In the upcoming school year I'm looking to get my act together so I can glide through worry free.