Check out the final routine at the end of the movie for the Clovers. Watching carefully, approximately 20 seconds into the routine you will see two girls on the left hand side running face to face into each other. If this had been a proper competition they would have lost because it was a major error in the routine.
When Torrence, Les, Missy, and Jan are driving in Les' car after picking Missy up, watch Les. He is constantly looking in his rearview mirror. This is because there is a cop car pulling someone over behind them.