Aye, I myself don't organize much and it's caused me grief before.

Simple advice: Keep a homework planner.

Write in it what homework you have and when it's due. This is essential if you don't want to end up forgetting something.

Use either one big binder or several small ones to store everything you get and every note you take. If you use one big binder then divide it into subjects, if you use many smaller ones then have one subject per binder.

Don't just stuff stuff into the binder or your textbook (I'm guilty of this), it's fast, yes, but it makes it a pain to find stuff (or, more of a pain then it needs to be) and stuff gets lost/damaged more often.

Don't leave homework until the last minute (also guilty of this), stuff thrown together at the last minute is never as good as stuff you've spent quite a bit of time on. It's the difference between an "average" mark and something in the 90s.

Finally, learn all of this now. Get into the habit. In highschool (and moreso university) being organized is essential, and it's much easier to do if you're used to it when the workload is less.


Edit: avyuir beat me to the punch.

And yes, a USB drive is an incredibly useful tool for schoolwork. If you're not in highschool then you probably don't need one yet, but they are in invaluable way to get reports to and from school without any hassle. Don't rely on e-mail, since most schools have draconian anti-e-mail policies.

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"Science is the poetry of reality." ~ Richard Dawkins