Factual error: While the problem with refuelling the SR71 is a real one for D.A.R.Y.L., he is never going to get that far. The SR71 had no self starters and required a trained crew with a starter generator mounted on a truck to get the engines going in the first place. D.A.R.Y.L. just pushes a button and away he goes. Not likely.
Continuity mistake: In the scene where Lyle and Ursula slide through the river then over the falls, when they go over the waterfall they are both dry.
Revealing mistake: When Macaulay Caulkin has all his friends over and they are riding the rollercoaster there is a section of it missing.
Suggested correction: The "missing" track is the car loading track for the station.
Other mistake: When Skinner calls his lawyer he never dials the phone.
Visible crew/equipment: When Newton is playing with the robot arm and the piano you can clearly see wires attached to the top of it controlled by the puppeteers.
Other mistake: When Chozen is buying vegetables from the villagers, one of the weights from the scale is knocked onto the ground. Daniel picks it up and realises that its not a real weight and breaks it in half. If Chozen wanted to cheat the villagers when he weighed their vegetables, he would need weights that were heavier than normal, not lighter plastic ones. Lighter weights would mean that Chozen would need to add far more of the light weights to make any amount of vegetables balance out, therefore he would be paying more for the vegetables than they are worth.
Continuity mistake: The band-aid on Jill's doll disappears and reappears several times.
Continuity mistake: When Joe gets injured and he insists the back-up quarterback goes in, he takes his wristband with all the plays on it off, so it can be given to the back-up. When the back-up quarterback is shown running on the field, he does not have it on, but when they show the back-up on the field, he does have the plays wristband on.
Other mistake: While the wizard is speaking near the portal, a ghost image of him appears to the left.
Continuity mistake: When Conrad first puts the spider lock in his pocket it is put in his left pocket, but when he takes it out, he takes it out of his right pocket.
Other mistake: It was established in the first Mask that the mask does not work in the daytime, but it works during the day in this movie.
Visible crew/equipment: The furry suits the "mole men" are wearing clearly show the zippers up the back when one of them is going down a well.
Revealing mistake: When Charlie and Grandpa Joe drink the fizzy lifting drink and are floating in the air you can see the hook that is connected to the wire that Charlie is being held up by.
Continuity mistake: As Jack Kelly rides the horse near the end of the "Santa Fe" sequence, his hat is waving behind him. When it cuts to a different angle the hat is on his head. Note: This was a specific detail put in by the director, symbolizing the boy's mental transition from New York to Santa Fe. However, it failed and is commonly seen as an editing mistake.
Continuity mistake: When he sees Meg in the river of death, he reaches down and touches it. Then, when he jumps in, he makes a dive of at least 50 feet. (01:11:25)
Continuity mistake: After Spike chases Jean-Claude out of the church, the parents and their kids stand outside. Chuckie is in his father's arms holding his Wa-wa (teddy bear). They go back inside, where Kira gives Chuckie that same missing teddy bear.
Continuity mistake: During the archery constest, in one scene Prince John has a ring on his right paw with no jewel, then all of a sudden the jewel appears. a few scenes later he has three rings on that paw, and later he has no rings at all.
Continuity mistake: When at the poolside of the Bonaventure Hotel, Adam looks at one of the express elevators ascending. Then he turns and runs for the elevators, followed by the blue team. Miraculously, both elevators are now at the bottom floor. (01:40:55)
Continuity mistake: Near the end of the movie when the 'false' Buzz Light Year is running along the air conditioning ducts his 'New Utility Belt' disappears then reappears again. (01:01:55)
Revealing mistake: When the boys' rival team challenges them, all the boys throw their gloves down, except Yeah-Yeah. When they all go to pick them back up, Yeah-Yeah has to pretend to pick it up.