Hopkins was given just four weeks to shoot and a further four weeks to edit the film. This meant that he had to shoot on one stage while the crew dressed the other, so they could shot almost continually. After he made it, the studio was so impressed that he was given the task of directing Predator 2.
When Alice wakes up from her nightmare in the asylum, and Robert Englund appears beside her in bed and pins her down, originally he said, "There's no such thing as safe sex." The line was excised from the film.
The famous song is changed. Original: One, two, Freddy's coming for you. Three, four, better lock your door. Five, six, grab your crucifix. Seven, eight, gonna stay up late. Nine, ten, never sleep again. Edited: One, two, Freddy's coming for you. Three, four, better lock your door. Five, six, grab your crucifix. Seven, eight, better stay up late. Nine, ten, he's back again...
The graduation sequence was cut down significantly to speed up the pacing of the film. As a result, there are several continuity errors. Among the cut footage was Dan's graduation speech, dialogue between Greta and Racine, a rap between Yvonne, Alice, and Greta, additional dialogue about parents and future plans, and a scene in which Alice's father gives her a camera she had been saving up for as a graduation present before she went to Paris (if you watch closely, you can see Alice hand her father a camera before they go to take the group picture).
When Alice and Mark look through the pile of newspapers, for a moment, the camera is set on an article regarding Amanda Krueger's death. In this article, Robert Shaye (Producer) is quoted as he says: "She was a victim of the evil within us all. I hope she will know peace in the life hereafter".
During the sequence in which the nun (Amanda) is raped by the criminally insane, Robert Englund is wandering around in the background without his Freddy makeup - including one shot in which the camera lingers on him for a few seconds.
On the door to Dr. Moore's office, just below his name, the name "Dr. Talalay" can be seen. This is a reference to Rachel Talalay, who had been involved with the series since the beginning in various capacities, most notably in directing Freddy's Dead: The Final Nightmare (1991).
The trivia items below may give away important plot points.
All death sequences were cut down significantly in order to avoid an X-rating. Dan's original motorcycle death was longer and contained much more gore. Many sequences showing Dan's face racked in pain were cut, along with his screams and Freddy's laughter. Scenes which are seen on screen for only seconds are minutes long on film. The entire sequence is much longer, and the timing of Freddy's quips are different. Greta's dinner scene was also edited. Originally, Freddy filleted the Greta-doll with the claw-glove causing it to spurt blood everywhere and then force-fed her its innards. Shots of the guests laughing were cut. Also, after Freddy said, "You are what you eat," she looked down and realized he had gutted her and was feeding her mush from her own stomach. This explains why the Greta-doll in Mark's dream is bleeding from its torso. Finally, Mark's demise is also cut. As Freddy shreds the paper in the unrated release, his face is animated and shows him screaming along to his cries of pain until Freddy cuts his paper head off. All three scenes can be viewed unedited in the original unrated VHS release.