Revealing mistake: When John tries to stop the van while Maggie is driving, because he sees the small girl in the road, as the van screeches around the road, you can see the road is covered in tyremarks from previous takes. (00:20:10)
Continuity mistake: When Freddy is controlling Spencer in the video game you see from Freddy's view that his legs are crossed on the table. When it cuts to in front of Freddy he has one foot only on the table. (00:42:25)
Continuity mistake: When John Doe is hit by the bus you see the stunt double holding onto the bus. In the next shot you see John Doe holding his hands to the front window of the bus.
Revealing mistake: In the memory scene, young Freddy kills a hamster with a hammer. But you can blatantly see that he hides the hamster under the table and then pretends to hit it with the hammer. (01:10:20)
Suggested correction: I just watched the scene in question, and he most certainly does not "blatantly put the hamster under the table." In fact, the scene is filmed in closeup and you can't see where he puts the hamster, but the motion of his arms seems to suggest he puts it directly down on top of the table.
Wrong. I watched this scene carefully and I saw young Freddy hiding the hamster under the table. It's much too obvious, even without slow motion. This entry is correct. This is a mistake.
Continuity mistake: At the start of the film on the plane, there is a woman sitting next to John Doe whose glasses go from being on her face, to then hanging down on straps around her neck, then back on her face between shots, just before she flies out the plane roof. (00:02:45)
Revealing mistake: Right before the John Doe gets pulled through the roof of the van by the dream parachute, you can see the premade cuts overhead for the stunt person to be pulled through.
Continuity mistake: When John and Maggie are at the old school, there is a teacher talking to a class which isn't really there. The teacher stands by the left side of the blackboard, which has large crosses drawn on it, in rows. It cuts to a closeup and the crosses are now smaller and more scattered. (00:27:25)
Continuity mistake: When the doctor is talking to John Doe, you see her grabbing his arm. Also there is a man in a green shirt passing by them. Then it cuts and she grabs his arm again. The man in the green shirt is gone but now there is woman in black where the man should be. (00:19:25)
Continuity mistake: John opens the window to find out the house is falling, and a large object goes flying through the window next to the bed, smashing out all the glass and all the wooden frames. Seconds later all the wooden frames are now repaired, however all the glass is still missing. (00:03:45)
Revealing mistake: After Freddy stretches the blackboard vertically, it switches to a closeup shot of him peering out from the side of the board. If you look closely at his glove, you'll see clear plastic caps on the tips of the knives. You'll also see them when he scrapes the board with his pinky and the final time he runs his hand across the board. (00:36:30)
Revealing mistake: When Freddy controls Spencer to the top of the stairs, Spencer stands right at the edge of the top stair, and leans forwards. As he does so, if you look at his shadow on the wall you can blatantly see the shadow of the harness and thick wire attached to him, keeping him from falling. (00:45:55)
Continuity mistake: At the start of the film, when John is in the airplane, the position of the white cloth on his seat headrest continues to change. (00:01:35)
Continuity mistake: When John goes flying off of the bus, into the "real" world, he hits a large, jagged, uneven rock. Later when he awakes the rock is very smooth and rounded, obviously a different one. (00:07:25 - 00:08:05)
Continuity mistake: When Freddy is standing above Carlos in his dream, he drops many pins from his hand. When it shows the pins falling, you see Carlos with his hands to his sides, but when it shows Carlos, his hands are over his ears and repeats several times.
Continuity mistake: When Freddy is about to cut over the parachute you see him move the blade close to John's hand. When it cuts, Freddy's blade has moved further up. (00:50:10)
Continuity mistake: When Maggie gets out of the cellar you see her with nothing in her hair. Suddenly she has leaves in it. (00:42:50)
Continuity mistake: When John walks up to the bus ticket booth, the booth's glass screen is covered in streaks of blood. During the differing shots from inside and outside the booth screen, the amount and position of these blood streaks keeps changing. (00:06:35)
Continuity mistake: When John wakes up in his room (which turns out to be falling through the sky) in the initial shots of him on the bed, the items (train models, books, etc.) on the bedside table continue to differ. (00:03:10)
Continuity mistake: In A Nightmare on Elm Street, Mrs. Thompson tells Nancy that a trail of gasoline went through the boiler room, out a door and set the entire place on fire. In this movie, a molotov cocktail is thrown through a window.
Other mistake: Why hasn't there been a mention of Freddy having a child in previous films? Couldn't be because they covered it up, as soon as Freddy was discovered to be the Springwood slasher the media would have been all over him and his family.
Suggested correction: Throughout the entire series, it's shown that there's sort a miniature conspiracy going on where the people of Springwood have been trying to make everyone forget about Kruger, including actively suppressing evidence. It's possible that when he was initially caught, the media was aware of his daughter, but not only would it not have been that big a deal (they were focused on him- not his family) in the decades that have passed since his original "death", the information was likely covered up or ignored in favor of trying to make everyone forget about it. (Hence, even Maggie doesn't know Freddy is her father.) Furthermore, the fact he has a daughter has basically no impact whatsoever on the story thus far, so it makes sense it hasn't been brought up before.
It has never been shown in any nightmare film that there is a cover up conspiracy until Freddy vs Jason (which takes place 5 years after this film), and that cover up begins after the events in this film, evidenced by many characters saying it's been quiet for 5 years.
