Deliberate mistake: Many times Pocahontas's hair blows in the wind, even though nothing else moves in the shot. From the way her hair moves, the wind should be strong enough wind to move something else, but not even John Smith's hair moves.
Deliberate mistake: The lake that the girls splash about in is very shallow, as they easily stand and play in it. Roberta does a head-first dive from a high tree, into it. There's no chance she wouldn't have hurt herself. (00:32:35)
Deliberate mistake: When the house is splitting in two, the board game should have fallen long before it actually does. (01:25:25)
Deliberate mistake: When Matt is spying through the telescope on Casey's argument with her parents, you can hear Casey yelling "No no no" and hear her bedroom door slam, etc. This is all from Matt's point of view from the telescope - it would have been impossible for him to hear any of that, being such a far distance all the way across the lake.