Plot hole: During the end the murderer is thrown out the front window of the building. The students leave the building through the front door, but yet there is no body, and that doesn't seem to bother them!
Continuity mistake: At the end of the film, Paul went in the house when it was raining, but his coat is not wet.
Continuity mistake: When the killer has hanged Damon in the tree and smashes the front window of the car, the girl in the car is backing, and when she does that the killer falls off the car, and then you can, if you listen carefully, hear a mans voice "say" something like "uff". The killer is a girl but the stuntman is a man.