My friends... I'm torn...?

Grade 7? Please, you are way too young for such serious drama. Stop making such a huge deal out of this! If I were you, I would stay in the cl you were placed in and suck it up, because in life you will face many situations that you don't necessarily want to be in. You'll make new friends and still see your old ones. If you really don't feel comfortable then move to the other cl and ignore what the little morons say about you. Seriously, it's not that difficult. It's just seventh grade.