Continuity mistake: Near the end of the movie, when Parker and Hunt are on the bus going to the contest, you'll see that Parker's hair is in waves. But when she arrives at the studio, her hair is VERY curly. Its not likely that she had time to change her hairstyle THAT drastically if she was pressed for time as she very clearly was.
Continuity mistake: Near the end of the movie, when the girls are trying to get to the dance contest, they are running through traffic, on top of cars, etc. Janie's hair changes with each shot. Sometimes it's up in a clip, other times, it's down. Plus, it's either really frizzy in one shot or kind of curly in others. Her hair changes drastically with every shot. Pretty funny.