When the Jonathan Reeves and Cooper are chatting in the theater, you see Eric coming down from the jump solidly in the background. In the next instant he has fallen over and injured his ankle. His landing from the jump shows no imbalance that would lead to an injury.
When Cooper is showing Charlie a move the front of his shirt is dry. In the next shot his shirt has a large sweat mark.
When Charlie and Jody are looking in the paper, Charlie has his arm behind Jody's head. When Jonathan gets onto them for talking, he moves it down, but when Cooper comes over and pulls the paper down, Charlie's arm is behind Jody's head again.
As Jody and Eva leave their room to smoke, the number on the door says 903C. When they run into Eric in the hall, he tells them to "come downstairs" to smoke. When the three arrive at his door, the number is 1103C.
In the beginning of the film, when Jody and Eva leave to smoke, the number on their dorm door says 903C, later when Jody, Maureen, and Eva leave to celebrate Eric's birthday, their dorm door says 903A.
Maureen's mother comments that Juliette's father managed a Walmart in New Jersey ("Perth Amboy"). However, the first Walmart in New Jersey didn't open until 1991.
During the last ballet sequence that has Jody dressed in red, in the beginning shot her point shoes are pink. In all shots afterward, they are red. This is because she is wearing pink shoes the entire performance leading up to this, and as the camera pans down her body and back up, she is in a new outfit with new hair and makeup. This is a transition to let the audience know without showing it, that there has been an intermission and Jody has changed.
The audience that watch the students' performance at the end of the movie is exactly the same as when the students go to watch the ballet at the beginning of the movie.
When Maureen is throwing up in the ladies room, she can be seen through the door and isn't really bending over the toilet but is instead standing up and making puking noises.
During the warmup of Jody's extracurricular dance class, the teacher says, "Let's get ready to get down and contract!" Her mouth does not match her words. She is actually saying, "Let's get ready to get down on the floor!"