Different

Different: An American Girl Movie about Acceptance, is about a girl named Rebecca Hansen (played by Marisol Luna) who has autism.

Youtube Description
"ABOUT DIFFERENT Rebecca is well, different. She loves her dolls, likes to give to the poor, and, oh, she has autism. She only has Clara Holland or a friend, so the whole "popularity contest" aspect of Student Council elections would make Rebecca lose, but when she befriends new kid Holly, Rebecca decides to give it a shot. Changing the world is what she wants to do, right? But when a mishap with the permission slip happens, the principal kicks her out. The principal hates Rebecca because she's different. Pretty soon, Rebecca decides to protest at the election. With only Clara and Holly beside her, will the principal decide that being different is good?"

Source: https://www.youtube.com/watch?v=sSiG51gogsA