Continuity mistake: When Beth and Jam hit heads to pick up his drumstick, she is holding the stick in her right hand. Then next scene, she's rubbing her head with her right hand and holding the stick in her left hand. Then they go back to the original scene and she hands him the drumstick with her right hand.
Continuity mistake: In the scene where Trip throws the pizza out the window of the car, it is full daylight. When Hawk puts the rock on the pedal of Kenny's car to make it drive itself into the ditch, it is sunset. In the next scene, when the guys are celebrating, it is full daylight again.
Continuity mistake: While the four guys are on their way to Detroit, Trip is hanging out of the sunroof. In the next few shots, you can clearly see that the car has no sunroof for Trip to hang out of. [The Volvo does have a sunroof the whole time, it is actually a moonroof with clean lines that are hard to notice.]
Continuity mistake: In the toilet scene one cheerleader pulls her panties down. They slide to her feet, but in the next shot they are a good 15cm up from her ankles. Unless she can make things rise with her mind, that's not supposed to happen. Also when her panties slide down her legs there is a sound of someone lifting a toilet seat, but she is already sitting down.