Continuity mistake: After making the mud-pie Fred jumps into his box. In the closeup as he lands in it and Elizabeth closes it, you can see Elizabeth has pink trainers on. In the previous and following shots she has white socks on. (01:02:50)
Continuity mistake: When Maurice is tossed out of the tavern we get a nice view of the front with its large hanging sign, but after Gaston whispers his plan to LeFou once again we see the front, which is quite different. The sign is gone, and now there are horns hanging on the awning, etc.
Other mistake: When Gomez begins to flip through his desk calendar, we see that "today" is Thursday, March 28, 1991. He then turns to the date of the "next quarter". The left hand page shows Thursday, August 8, but the right hand page shows Tuesday, September 9. (00:11:15)
Revealing mistake: When Bill and Ted leave the house with their "bad" selves, Keanu Reeves' double is seen as they move past the camera. (00:21:20)
Continuity mistake: When Peter recalls himself alone in the rain with a teddy bear by his side, the bear is sitting upright in the first shot, but resting against the baby with its head skewed in the following angle.