Friends not sharing the same academic goals

I’m not sure if this pretentious but I guess I’m known as the ‘smart one’ in my friendship group because I actually take school seriously. I don’t think they’re going to fail their GCSE’s but they’ve never revised for any mocks or tests and get shocked why they do badly. They don’t make fun of me for actually revising but from their tone/language or body language I feel like they think I’m a ‘nerd’. I don’t really care about that but what annoys me is that when it’s time for mocks or tests they all come to me asking for help knowing that I have revised, expecting me to teach them and that really makes me mad. They never speak to me outside of school but when it’s time for exams that’s when they remember I’m their friend.