Organization is key.
Make sure you have all the supplies you need. I suggest 3-ring binders for your core classes and folders with prongs for any elective classes. Make sure to have college ruled paper and dividers if the teacher asks for you to have them. If your teacher likes to lecture, like most of mine, have a spiral notebook for notes. The pages are less likely to rip out than loose-leaf. Keep papers in chronological order, they'll be easier to find later when studying. If your binder starts to get full, take out the old papers and put them in another binder to keep at home. This way you won't have to lug them around, but they will be there when studying for semester tests.
School DOES matter.
Most high schoolers believe that school doesn't matter. That they can fail a class or slack off and it won't affect them in the future. The truth is, school IS important. You need it to have a good resume, and you need it to get into a good college and later get a good career that will support you for the rest of your life. It's important to have fun and have lots of extra-curricular activities, but school should always be your number one priority. With that being said, extra-curricular activities are also good with college resumes as well such as Student Senate, FBLA, Teachers of Tomorrow, and pretty much any club your school offers.
A social life is just as important.
You endured 5 painful days in a place some call prison, and the time has come to cut yourself some slack. During the weekend go somewhere fun and have a blast. Even if you don't have many friends, spend the weekend relaxing and doing what you like to do. Let yourself loose and revitalize yourself so when Monday comes, you're all partied out and ready to focus again. But remember that school is your top priority, so don't do this if you have piles of homework on the weekend. Otherwise you'll end up like me trying to cram a giant essay in one night. Exactly,...