Help!!! Advice on what to do?

So in literature class we do these thing called SRA, you read an article and then answer the questions. Our teacher puts the answer key face down on our desk so there's no need for a commotion when a whole bunch of people get up to get their answer key. The thing is everybody is cheating, and the teacher isn't noticing it. I don't cheat cuz it goes against me. I'm a goodytoshoes or what ever they call. I'm getting bad grades cuz their really hard while my classmates effortlessly get 100s. I rly want to tell the teacher, but then the whole class would hate me. They know that I would rlly like to tell on them, so I don't. I can't leave an anonymous note to my teacher either.