Sorry to hear that Tony. It's horrible to be made fun of.
As some have already mentioned, people who bully others are really insecure themselves. They try to make themselves feel better by pulling others down, or by doing what their friends do to try to fit in. If they can make you feel embarrassed or insecure, they feel better.
A great way to respond is to show that you're confident with who you are and proud of the things you are good at. But also that you don't take yourself too seriously and don't mind laughing at yourself a bit too. Who knows, laughing at yourself a bit might surprise them enough that they stop. And remember, at the end of the day, they don't have any lasting power over you. After a few years you probably won't even remember them.