What do you need to do in order to do better? Do you need more time to study? Are you studying right? Do you need tutoring? Extra help from the teacher?

Try to figure out what is going wrong, and find out how to fix those issues. Talk to your teachers, and try to figure out what is causing you to get Cs. If the material is hard, study more, or get a tutor. If you need to cut back on your social life, or on tv, then do it. You need not only to study, but to study effectively. Go to all your classes, all the time. Speak up in class. Do your reading and homework. Ask questions, either in class or afterwards, about things that confuse you. Don’t be afraid to ask for help.

Since you keep getting C’s, I wonder if something about your study skills can be improved. Talk to your guidance counsellor, and your parents. See if there are any private tutoring centers around you, like Sylvan, which can help you improve your study skills across the board.

Also, your writing skills are just so-so. A tutor, either through your English teacher or else through Sylvan, can help you improve those skills. Working on your study skills, and on your writing skills, may improve your grades across all your classes.

Make your high school classes be like your main point in life right now. See what you can do to raise those grades.