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: When Jeff and his father are talking at the dinner table and his father is convincing him to be in the contest, each time the camera cuts to either one of them the sugar bowl on the table either has the lid off, or on. It changes every cut. Same thing with their mugs.
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.
Continuity mistake: In the audition for "Dance TV" after Helen Hunt's character has been cut, she moves behind the other auditioners to argue with her dance partner. Kneeling in front of her, beside a girl in a pink leotard, is supposed to be Lee Montgomery, but his stand in's face is visible throughout the scene, right up until his close-up, before he stands up.