I think you look pretty! And I'm not just saying that.
Sometimes, well, most of the time, kids will pick up on small differences in the way you act (for kids with aspergers, that usually means small differences in the way you interact with other people)
the kids can't quite put their finger on what is different about you, so they make fun of something easy, like the way you look. (Who isn't self-conscious about how they look?)
Does that make sense? My little brother is the same way- -he's quite good looking, but gets made fun of because he acts a little differently than most kids, even if it's not really obvious.