Continuity mistake: In the opening scene, on the floor there is a toy train on circular tracks when the monster sneaks in. When the monster trips backwards over the ball and skateboard then falls onto the jacks, the train and tracks are gone. (00:01:49)
Continuity mistake: At the beginning when you see the monster in the testing room from under the bed with the glowing eyes, you also see the soccer ball on the left side of the screen. This shot takes place on the side of the bed. After the monster gets scared, he backs up kicks the soccer ball, but it is now at the foot of the bed in the middle of the room. (00:02:35)
Continuity mistake: At the beginning when the monsters are at the testing room, you can see the boy in the bed seeing something opening the cabinet. He closes his eyes and opens them up again to see a sweater sticking out. But when another monster sees what he does wrong on the tape, the sweater isn't sticking out anymore. (00:03:40)
Continuity mistake: At the beginning of the film, we see Sully asleep in his bed and the alarm clock/radio on a bedside cabinet to the right. Later, when Boo climbs into Sully's bed, the clock/radio isn't there anymore. (00:04:50 - 00:32:30)
Continuity mistake: There is a purple chair and a green chair in Mike and Sulley's apartment. The green chair disappears when they are at the apartment with Boo later. (00:05:45 - 00:27:50)
Suggested correction: Didn't they use the chairs fabric to make Boo's disguise? The chair would have been ruined.
They only used Sulley's chair to make a costume for Boo. Mike has his own chair but we are never shown as to where he keeps the chair. He may have put the chair somewhere else in the apartment so Boo wouldn't her germs all over it.
Continuity mistake: Before going to the Scare Floor, Mike goes to get his paperwork from Roz. The paperwork first faces 5 o'clock direction. A few shots later, the papers suddenly face a 12 o'clock direction. (00:11:25)
Continuity mistake: At the start of the workday, Randall opens the first door with the knob on the left and hinges on the right. When he comes back out, the knob is on the right and the hinges are on the left. (00:14:45)
Continuity mistake: When George comes out of the door with the kid's sock stuck to him the sock's toe points inward toward the middle of his back. When the CDA rushes in to remove it the sock toe faces outward. (00:17:40 - 00:18:25)
Continuity mistake: After the Scare Floor shuts down at 6:00 and Sulley goes back to do Mike's paperwork, the clock reads 5:48. After he returns again to put Boo back, it clearly shows 5:48. Finally, after Randall leaves and Sulley leaves the Scare Floor for the restaurant, the clock reads 6:48. (00:22:06)
Continuity mistake: When Sulley places the menu on the table he puts it face down (logo first), then when he lifts up the table, to quickly get Boo, the menu is face up. (00:26:05)
Continuity mistake: In the apartment, Sulley leaves a trail of Kreature Krisp for Boo to follow. The first one he places is white, which becomes green in the next shot. It's obviously the same one in both shots because of its position in the doorway. (00:31:00)
Continuity mistake: Boo shows a drawing of Randall. First, it's held in a portrait position, then in the reverse angle, it is now held in a landscape position. Then back to portrait position in the next shot. (00:31:30)
Continuity mistake: When a green monster named Frank was walking out of Monsters, Inc. on the second day, take a look at what's behind the door - It only shows passages to scare floors, but when Mike and Sulley (holding Boo in costume) walk in, the CDA is all over the place. (00:35:05)
Continuity mistake: When Mike, Sulley and Boo are walking to the Scare Floor after leaving the locker room, Mike's feet and legs are soaking wet. His feet are suddenly dry by the time they reach the Scare Floor. (00:38:45)
Continuity mistake: When they go to the Scare Floor to put Boo back in her door, Mike swipes the card key and the numbers "240492" appear on screen. In the next shot, the numbers on screen are now "43496". (00:39:10)
Continuity mistake: When Sulley believes Boo is in the trash compactor, a cube of garbage comes out. In the first shot of the cube, the light used to make the "eye" is seen sticking out. Then as the conveyor belt stops, the light is now laid down on the cube. (00:44:20)
Continuity mistake: When Sully and Mike are talking in front of the Abominable Snowman, and Mike starts throwing the snow cones at Sully, we see the snowman covering one of the snowcone holes with his thumb, while from a different angle it seems as though his thumb is between the two holes and the hole that he had just covered has an empty snowcone wrapper in it. (01:00:35)
Continuity mistake: When Mike is bringing Sully to the fixed door he has no slivers or band-aids on his hands, then when he says "it was a lot of wood to go through" you see he does. (01:24:10)
Continuity mistake: During the ending credits, they show Mike and Sulley redoing their "musical" number in front of all the monsters on the scream floor. During this Sulley blocks Boo out of the way by pushing her behind him. But when Sulley starts to dance, Boo has disappeared. (01:28:50)
Continuity mistake: At the start, when the simulation is terminated, as Phlegm pulls a jack off his back, the large checkered rug at the foot of the bed is gone. It should be seen on the floor in front of him, in this shot facing the wall as it goes up.
Suggested correction: Sully may have unplugged the alarm clock and put it somewhere else, especially when there's a "dangerous" child in his home, and he wouldn't want his things to get contaminated.
This correction is a stretch. If he doesn't want his things contaminated, why not remove the pictures and lamps? Why let her sleep in his bed with his blankets?
Bishop73