Continuity mistake: Jim fires at the ceiling and rubble falls on Ed's head. A shot later he is standing tall unharmed and clean and the roof falls on him again.
Suggested correction: Incorrect. The roof doesn't collapse all at once - a small piece first falls and hits Edward on the head in the first shot, then the rest of the roof falls down a few seconds later in the second shot. You can even see the small piece that hit Edward in the second shot if you look at the ground. He also isn't "standing tall unharmed and clean" in the second shot. Look it up on YouTube (search for "Edward Scissorhands (1990) - Jim Attacks Edward (4/5) " on the Movieclips channel), and pay attention around 0:54.