You could speak with your pastor or your parents about some of the things you've thought about. You don't have to tell them about what you've been doing at school. Or if you are sure this won't go over well, you could speak with a pastor on your campus. Think about the pros and cons of your religion. Sometimes, it is better to recognize and reconcile with what you do not believe in, agree with, or support, than to discard your religion lock, stock, and barrel.
Faith is an extremely personal matter.
You may decide to keep your faith, but not your religion. With time and patience, you'll decide what is best for you.