Other mistake: When Taryn turns into a punk and walks down the alley way, you can clearly see Freddy's back along the bottom of the camera shot as if he is trying to pass the camera for the next shot. This happens as Taryn looks down the alley. However, if that was meant to happen, wouldn't she have seen Freddy, and not have been so scared when he approached her from behind?
Continuity mistake: When Max turns off the lights, the switches are already down - he doesn't move them in any way (neither up nor down) and therefore hasn't made any actions that would alter the current lighting situation, however the lights turn themselves off anyway even though it is apparent the switches were not moved. Nobody else moved any lightswitches either.
Continuity mistake: In the scene where Freddy turns into a puppet, he cuts his own strings with his knive fingers to get down and as he falls you can see some strings still attached to him, but when the shot changes and he lands on the floor, there are no longer any strings attached to him.
Continuity mistake: The day Kristin is admitted into the hospital, she is screaming and fighting with the staff. She then cuts Max on his right inner arm with a scalpel. In the next scene where Max is introducing the kids to Nancy, Max has a very small band-aid where Kristin cut him yet the band-aid is on the outer part of his arm by his elbow.
Plot hole: The group talks about Phillip's death. The doctor says Phillip's death was a sleepwalking accident, nothing more. Then the other doctor says it was suicide. How do you explain either situation when the door was padlocked with no way out to the very top of the building where Phillip fell?
Plot hole: The TV-watching girl is killed when Freddy shoves her face first into a TV set. (one of the more creative movie deaths.) But the thing is, all the other deaths have been set up to look like suicides if not accidents - this one was obviously foul play, since there's no way she could have launched herself into the glass of a TV screen hard enough to break it. We see that her body is found this way, but they make no inquiry.