Continuity mistake: When Dan is in the woods the amount of wood he is carrying decreases. (00:25:35)
Continuity mistake: When Tina uses her psychic power to hang Jason, the size of the hole he falls through changes between shots.
Continuity mistake: When the girl is thrown out the window you see her falling with her right shoulder first while crouching. In the next shot she falls directly onto her stomach. (01:02:05)
Continuity mistake: When Jason throws the girl out the window he throws her with her back first. When it cuts from the outside she is coming out the window face first. (01:02:00)
Continuity mistake: In the scene Robin tells Maddy she's going to get David, a cup of coke on the counter vanishes for a shot, the green napkins move around, and the blue flowery pattern on the bowl disappears and reappears. (00:30:50)
Continuity mistake: When Michael goes to the bathroom in the woods, Jane is standing next to the road. In the reverse shot, she is standing next to a tree.
Continuity mistake: When Jason shoves his fist through Dan in the woods his fist is bloody, but when he kills Dan's girlfriend, the blood is gone. (00:27:00)
Continuity mistake: When Jason swings the girl in sleeping bag against the tree, he grabs the head end, yet the head end is the one that hits the tree. [This is fixed and not a mistake in the uncut editions (theatrical and new release dvd) because the uncut scene has Jason taking six swings with the sleeping bag against the tree, including the head end.] (00:26:50)
Continuity mistake: Just before Jane is killed in the woods, you see her standing with her arms crossed from the back. When it cuts in front of her she is crossing her arms again. (00:18:50)
Continuity mistake: When Tina battles with Jason, the height of the basement roof drastically differs.
Continuity mistake: The bullet hole that Sheriff Garris shot above Jason's eye in Friday the 13th Part VI: Jason Lives is missing from the mask in this movie. (00:14:30)
Continuity mistake: When Tina is driving, she swerves to avoid Jason. The trees that she almost hits change between shots. (00:43:15)
Continuity mistake: When David says "The neanderthal man...," he puts his right hand on the girl's chest. When it cuts back his arm is no longer there. (00:53:35)
Continuity mistake: When Robin tells Maddy that she's gonna stick with the deal and "have a good time" she opens her arms up twice between shots. (00:33:10)
Continuity mistake: In the scene where Maddy hides from Jason, she is barefoot. In one shot she sees him, and bends down and grabs her shoes. In the next shot she picks them up once again. (00:49:00)
Continuity mistake: As Jason steps out of the puddle, his clothing is dripping wet. Then in the next shot as he walks after Tina, his clothes can be seen, dry. (01:10:50)
Continuity mistake: Tina's pink t-shirt that Mike notices by his feet, which fell out of her suitcase, is not actually there in the shot beforehand and simply appears. (00:09:10)
Continuity mistake: When Tina throws the plant at Jason it hits him in the chest. The next shot shows it hit him in the head.
Continuity mistake: In the shot where Sandra notices Russell's dead body lying on the shore, Sandra's trainers are lying right next to her shirt and shorts. In every other shot her trainers are nowhere to be seen on the shore. (00:35:50)
Continuity mistake: When Tina opens the door for Nick, the fridge door has magnets, an organizer and a cloth on it. Later when Tina's mum closes the fridge door everything is now off the door except for a magnet. (00:17:00 - 00:31:15)
Answer: Jason was dead at the end of Part 6, the girl used her E.S.P. powers to bring him back to life.