Continuity mistake: In the episode 'The 525 CrackerVac' the vacuum cleaner malfunctions (as usual) and Gromit challenges the device like in a duel. The scenery changes to orange like in a sunset and Gromit stands with his back towards the window. On the window sill you can see a cactus. Wallace is in the room near the door. The vacuum cleaner explodes and covers Wallace in ashes/dust. Wallace suddenly has the cactus on his head (also covered in ashes) and judging by the fact that there is a clean area behind Wallace on the wallpaper in the shape of Wallace with a cactus on his head he must have had the cactus on his head before the explosion, but we know he hadn't as the cactus was standing behind Gromit and Gromit stays clean after the explosion, so the cactus couldn't have moved. How did the cactus end up on Wallace's head?
Continuity mistake: One of the tiles comes loose when Wallace is walking across the ceiling in the museum. A few seconds later, the tile is flat against the wall again.
Continuity mistake: When Speedy rushes out to take all the cheese in the trap that George and Benny have put out for him he is seen wearing a sombrero; however, for the rest of cartoon he is hatless, repeat, hatless.
Other mistake: When Snoopy starts sneaking through the pumpkin patch, Sally is standing with her arms crossed and Sally's hand is painted blue while talking to Linus. (00:20:35)
Continuity mistake: When Sam points his gun at Bugs at Fort Knox, he says "But I can't take any chances!" and throws away the gun. In the next shot, the gun is back in his hand again.
Continuity mistake: When Scrooge walks into the Cratchit home at the end, there is a "Home Sweet Home" plaque on the wall. The shot then cuts away from it. The next time the plaque is visible, its lettering has changed.
Continuity mistake: When Minty arrives at the North Pole in a balloon, she passes Santa's house twice.
Continuity mistake: Charlie Brown's Christmas tree is never the same. When we first see it, it has three branches. Later, when he's carrying it, it has four branches. Then, when he tries to decorate it and it flops over, it has six branches.
Continuity mistake: After Wallace gives the woman the balls of yarn, the balls change position between shots.
Continuity mistake: A penguin uses binoculars rotated at a 90 degree angle, but the shot of the view through them is composed as if they were being used normally (horizontally level).
Continuity mistake: When the thumbs are in the car driving to the woods, in some shots their thumbs are out of their shirt a lot, but in other shots, they're in there all the way.
Continuity mistake: At her house and at the fair, Daisy's bangle bracelet repeatedly disappears then reappears and changes wrists as well.
Continuity mistake: When Wallace races to get crackers, check the packet's logo. When the camera angle changes it's different. (00:08:57)
Continuity mistake: When Snoopy is at the library, he picks out a book and you can see there is nothing on the front cover, but when we see a close up of the book in the next shot, the words "How to Perform Magic" have appeared.
Continuity mistake: When Jerry appears from the hair of the toy lion, you can see that behind him there is a decoration and some purple baubles. In the next shot, the decoration has disappeared and the baubles are now much closer to the lion.
Continuity mistake: When Jerry is pretending to dance with the placecard mascots at the restaurant, the last mascot he dances with initially has red hair, but when the two pretend to skate on the mirror, her hair is now blonde.
Continuity mistake: In order to tiptoe across the tacks without being hurt, Tom puts a metal gauntlet on his feet. At this point, you can see the floor is completely covered in tacks, but when Jerry and Nibbles are at the same spot a little later on, the tacks have disappeared.
Factual error: The adventurers witness Earth "rising" from behind the lunar horizon. Since the Moon is tidally locked, it always presents the same hemisphere toward Earth. Earth never rises or sets as seen from the Moon's surface; it stays stationary in the sky. No matter that no-one had travelled to the moon at the time - that fact can be deduced just by looking at the moon from earth, and noting that we only ever see one half of it.
Continuity mistake: Curly's shirt is stained with clay, yet he hasn't been hit in the chest yet.
Continuity mistake: As Gromit tries to get to the window with the bomb, he is stopped by being hit hard with a large metal oven paddle which swings in from his front right side. When we see Piella holding it, there is a Gromit-shaped dent in it, but it is dented the wrong way, bulging outward on the side he was hit with instead of indented.