Revealing mistake: When Jesse is cleaning out his room, he puts a tape into his tape player, and presses a button down on the top of it. But halfway though the scene of him packing his things away, you can clearly see the button is no longer pressed down, yet the tape still plays. (00:18:10 - 00:19:00)
Revealing mistake: When the crazy bird is let out of the cage it starts flying around. Then it explodes in mid-air. A split-second before it explodes you can clearly see the size of the bird increase by about three times. (00:28:15)
Visible crew/equipment: When Schneider is being dragged along by two skipping ropes you can clearly see two wires attached to his shoulders which are actually pulling him along. (00:34:10)
Continuity mistake: When the balls start to bounce of the shelves, in one shot a basketball hits some tennis rackets which are hanging on the wall and a few of the rackets fall off the wall, but in the next shot the tennis rackets are hanging back up on the wall. (00:33:05)
Revealing mistake: When Jesse and Lisa are reading the diary you see the pages in the diary are clean. Nothing is written in the pages they are reading from. (00:21:35)
Continuity mistake: When the bus starts to stop, a load of people get up from their seats and walk to the bus doors. But in the outside shot of the bus as it stops, nobody is standing up, and everyone gets up once again, heading for the bus doors. (00:01:40)
Visible crew/equipment: In the kitchen, when Jesse's dad says "I want that room unpacked by tonight young man," the camera pans around the kitchen table. Look to the right of the screen, you can see the elbow of a crewmember come into view. (00:06:30)
Continuity mistake: When Jesse's dad is talking about the air conditioning in Jesse's room, Jesse's sister puts the cereal box on the table. Then in the next wide shot she has the cereal box back in her hands, then puts it back on the table once again. (00:07:00)
Continuity mistake: When Jesse and Lisa first arrive at the boiler room factory, Jesse says to Lisa "How long has it been closed down?" And then Lisa replies. To the left of them you can see a large machine, which Jesse and Lisa are standing well away from. But as the shot changes, they are now standing right beside the machine. (00:42:20)
Plot hole: When Freddy takes over Jesse's body at the party, there are several people watching through the patio doors when he confronts Lisa. None of these people ever make a sound, even when they see Lisa have a knife fight with a horribly disfigured man with long knives coming out of his fingers. The other party goers are completely oblivious to Freddy's presence until he comes jumping through the glass doors.
Audio problem: When Jesse and Ron are doing press-ups on the sports field, Ron says "So what about you and that rich babe you've been cruising to school with every day?" You can see that Ron starts to move his mouth a few seconds after the words are spoken, and his mouth doesn't move correctly to the words being spoken either. (00:10:30)
Visible crew/equipment: When the bus closes the door and takes off you can see the reflection of the camera man in the bus. (00:01:05)
Continuity mistake: When the bus starts to speed up, it passes a stop with some people waiting there. There is a little girl on a tricycle waiting, and she is pointing to the bus, but in the next shot of her, her hand is down. (00:02:25)
Revealing mistake: When the tennis balls pop out of the tubes at Schneider, you can clearly see a hole cut into the bottom of each tennis tube. (00:33:15)
Revealing mistake: When the sausages catch fire at the party, you can see the flammable liquid surrounding and covering them. (01:00:45)
Continuity mistake: At breakfast, when Jesse's sister goes to sit where Jesse is about to sit, Jesse says "No!" to her and she sits back in her chair, still trying to get the plastic claws out of the cereal box. As she tries to get the claws out, she is holding the top of the cereal box with her left hand. Then in the next closeup of her, her hand is down by her side. (00:06:40)
Revealing mistake: At the end of the film, Jesse and Lisa react way too early to Freddy bursting out of the girl sitting behind them. (01:18:52)
Continuity mistake: When Jesse and Lisa are reading Nancy's diary, Lisa reads the first entry and it says all about Nancy dreaming of Freddy. The next entry that Lisa reads is about Tina being killed.If you remember in the first Nightmare, Nancy does not find out Freddy's name until after Tina is dead. The entries in the diary are not in order. (00:21:15)
Visible crew/equipment: When the bus is driving along the rocky desert and the sky turns dark, you can see two stage lights reflected in the back windows of the bus. (00:03:00)
Revealing mistake: Freddy bites Lisa on the leg. When she starts to kick him, you can see it's Lisa's stunt double.
Answer: I think the coach's death was a play on his character being at a S&M bar. People who frequent those places are usually into bondage and being dominated. Hence being tied up, and whipped with the towel. It also fits in with the homoerotic subtext throughout the movie.