Continuity mistake: When Morris is drunk and the dean of the school almost hits him, the first shot shows him with a cigarette dropping from his mouth, but in the next shot from the side the cigarette is still in his mouth.
Continuity mistake: When Kevin is putting on clothes at the car, the necklace that he is wearing goes from outside of the shirt to inside the shirt between shots.
Factual error: When the college students are shooting pedestrians with paintball guns, the guns don't have ball hoppers which hold the paintball ammo, hence no ammo. Yet when the camera angle changes, it shows pedestrians getting hit by paintballs.