Well, a class is, for a lot of people, just people who you're never going to see again for the rest of your life after one year or two, so unless you're specifically *friend* friends with one of them I wouldn't expect much.
It sounds like your class didn't do this out of spite, but were just being stupid and lazy. Tread with caution, there are many people like this. You are intelligent and charismatic, Summer. You don't need people like that in your life.