I Was A Non-blonde Cheerleader by Kieran Scott

Annisa Grobowski is used to starting over since her English professor dad is constantly trying out new positions, but in Florida she gets more than she bargained for. She is the only brunette in the school and manages to make enemies of the popular girls, who will decide whether she makes the cheerleading squad, all in her first day. Luckily there's a cute boy who's nice to her, too bad he has a cheerleader girlfriend.

Light, fluffy and all works out in the end.