Freddy's sweater was knitted by Judy Graham, the same woman who knitted Freddy's sweater in the original A Nightmare on Elm Street (1984).
Kyle Gallner suffered a cut to his abdomen when the glove Jackie Earle Haley had been wearing failed to bend back down, leaving one of the knives still extended. Haley didn't realize this until the scene was finished.
For his big scene in the opening sequence, Kellan Lutz chose not to sleep for a few days to get himself into character.
When Jackie Earle Haley was asked what put him in the right mindset to play Freddy Krueger, he said "sitting in the makeup chair for three hours. After that, you feel like you could kill someone."
Freddy says that the human brain will still function well over seven minutes after death. This is actually true, the human brain will function nearly ten minutes after death. Note: This is not true. If the brain is still functioning, you are, by definition, not dead. You may dying, but those are not the same things.