Bart Carny - S9-E12
Continuity mistake: Up until the point at which Skinner starts throwing rings at the block in front of the Spanish lamp, the block simply doesn't exist. It only appears once he starts throwing the rings.
The Simpson's 138th Show Spectacular - S7-E10
Continuity mistake: During the false ending to "Who Shot Mr. Burns: Part 2", Smithers moves position when Burns explains what happened.
Continuity mistake: The antenna from Homer's car disappears when he drops Mother Simpson at the gas station.
Continuity mistake: When Bart arrives at school in the bus, after Homer plowed the road for the bus, the sidewalk is covered in snow except for Martin's footprints. Then, when he gets out, the sidewalk has been shovelled, as there is no snow on it. Following this, Bart is pelted by snowballs, which sends him falling face-first into the sidewalk, which is once again covered in snow. (00:10:20)
Diatribe of a Mad Housewife - S15-E10
Continuity mistake: When Homer comes home in the Ambulance we can see there is a yellow logo on the back passenger door. In one shot it randomly disappears. (00:05:40)
I, (Annoyed Grunt)-bot - S15-E9
Continuity mistake: In this episode it is shown that Snowball I is buried in their backyard, but in other episodes, notable the one where Sideshow Bob becomes mayor, it is established that she is buried in a pet cemetary.
Continuity mistake: Nelson makes a hole in the Honor Roller during the finals. This hole disappears and reappears between shots. (00:20:00)
Continuity mistake: When Dave gives Homer the Bill Cosby book, the cover is light blue. When he reads the book in the garage, it is green. (00:09:40 - 00:11:30)
Continuity mistake: When Chief Wiggum finally climbs the stairs his gun is visible to be a black, old style revolver with a curved handle. In the next shot where he draws his gun, it is a grey, new style handgun.
Continuity mistake: When Otto is playing the guitar with bart in the middle of the night, there are close-ups of Otto whenever he is singing. You can see that the wall behind him is plain. However, when there is a wide shot of otto and bart, the wall behind otto has two tables leaned against them. (00:15:50)
Continuity mistake: When Bart uncovers the photo of the Simpsons behind the books in Lisa's locker, the books change between shots.
Homer vs. Lisa and the 8th Commandment - S2-E13
Continuity mistake: When the door is answered to Mr Burns and Mr Smithers, Barney is seen answering, who has orange sleeves. However when the door is opened, you can just make out a white sleeve, which could be none other than Homer's.
Continuity mistake: When Homer is showing his BBQ invites to the kids Bart comes and stands next to Lisa and points to the extra 'B'. In the next shot, he's back over near Homer.
Continuity mistake: When Homer first lifts the corpse up, it is wearing glasses. But when it cuts to the shot of the corpses' face, the glasses have gone.
It's a Mad, Mad, Mad, Mad Marge - S11-E21
Continuity mistake: When Marge is sitting with Patty and Selma talking about Becky taking over her family, Selma has some sort of drink. As the shots change, she goes from having half a glass, to a full glass, to having no drink at all.
I, (Annoyed Grunt)-bot - S15-E9
Continuity mistake: The cats' graves change position. When Snowball II is buried, they're away from the the tree and near the fence. When Snowball III is buried, the graves are away from the fence and Snowball is among the roots of the tree. (00:04:10 - 00:09:25)
'Tis the Fifteenth Season - S15-E7
Continuity mistake: Homer looks out of his bedroom window at the skating rink he has built in his back garden. Homer and Marge's bedroom is usually at The Front of the house. (00:13:50)
Continuity mistake: When Bart and Skinner are checking lockers, you can see in a wide shot that Bart needs to check seven lockers before he gets to Lisa's locker. However, Bart checks eight lockers and then opens Lisa's locker. (00:19:35)
Continuity mistake: In the cafeteria scene where Milhouse shoots a spitball at Kearney, in the shot when Milhouse says, "We have order, but at what price," Milhouse, Lewis and the bullies all change positions at their tables. You may have to watch this part several times to understand it. (00:16:45)
Burns' Heir - S5-E18
Continuity mistake: Burns' top hat disappears from the bath at the start.