
Bart Carny - S9-E12
Continuity mistake: In the end of the episode when the family has reclaimed the house and are cleaning up the living room. As Homer mentions about letting the Cooders stay, Bart tells Marge to get him away from the window. She is standing right next to the couch in the lounge but the very next shot she lowers her hands and pats the couch yet is now in the family room. (Note: There was a few shots that showed there was two couches so the mistake is with Marge suddenly moving not the couch.).
Lummie

Continuity mistake: When Edna waits in The Gilded Truffle, she checks her watch. In the next shot the watch has gone. (00:15:40)
Hamster

$pringfield (or How I Learned to Stop Worrying and Love Legalized Gambling) - S5-E10
Continuity mistake: When Marge comes home after the bogeyman incident, Homer trips over a footrest. You can see Bart sitting there however his pyjama's are a dark green color when before they were a bright green color. (00:16:35)
Lummie

Like Father, Like Klown - S3-E6
Continuity mistake: When Krusty rings his father, there are glasses on the bedside table. In the next shot they are gone. Meanwhile the other objects on the table have moved around.
OL1V3R666
Tree House of Horror VII - S8-E1
Continuity mistake: In 'The Genesis Tub,' when Skinner is grading the universe in the tub, his clipboard changes from brown to blue. (00:17:55)
Hamster

The Trouble With Trillions - S9-E20
Continuity mistake: In the scene where Homer is eating a hot dog just before the post office closes for the day, the vendor behind the hot dog cart has a apron over his shirt. The very next shot the apron has disappeared. (00:05:05)
Lummie

Continuity mistake: At the end of the episode, Homer puts twenty dollars into Moe's tips jar, but in the next shot the twenty-dollar note has disappeared. (00:20:40)
Hamster

Realty Bites - S9-E9
Continuity mistake: When Marge finds out the Mr Hutz does real estate, the 'For Sale' sign changes from black to red and then back again.

Tree House of Horror XII - S13-E1
Continuity mistake: In 'Hex and the City,' as they walk through Ethnictown, Marge has a handbag over her shoulder. But in the closeup when she says "Oh, listen.", the bag has gone. (00:01:15)
Hamster

Continuity mistake: When Krusty the Clown arrives at the beauty pageant his tie is done up. When he goes on stage it is undone.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5
Continuity mistake: When Homer is escorting his family out of the house to escape the Zombies, he leaves the door wide open, but in the very next shot it is shut.

Continuity mistake: While Bart starts the I.Q. quiz and is reading it out loud, his teacher says "Shh. Visualize it Bart." While this happens if you look in the background you can see the alphabet line. It starts out Tt Uu Vv Ww, then Bart's teacher blocks out some, then you see the letter T again. (00:04:50)

Life on the Fast Lane (a.k.a. Jacques to Be Wild) - S1-E9
Continuity mistake: At work, the salad in Homer's sandwich disappears when he mentions that 'she' made it.

Continuity mistake: When the pile of newspapers fall on principal Skinner, two garbage cans appear out of nowhere beside the door. (00:19:10)
Yoshi
Bart Gets Hit By a Car - S2-E10
Revealing mistake: After Marge has been in court, Mr Burns' lawyer says "Thank you very much Mrs Simpson", and when he does it, the top of his head above his glasses is less pale than the rest of his face.
OL1V3R666
Treehouse of Horror XV - S16-E1
Continuity mistake: At the beginning when Kang and Kodos's boss comes to have dinner, his stomach explodes leaving a hole, yet in the next shot the hole has vanished. (00:00:40)
Chaz1003
Continuity mistake: After Homer dodges the cannonball near the end of the episode, the blue platform that he stood on goes further away from the edge of the stage between shots, and when Homer hugs Marge the platform has disappeared and Peter Frampton's cooler has become closer to Homer.
OL1V3R666
Tree House of Horror V - S6-E6
Continuity mistake: In 'Time and Punishment,' when Homer exits the basement, he discovers Bart and Lisa are giants, and he then screams and runs back to the "basement" - however the same door that leads to the basement seconds ago, now leads to a green -carpeted room, and the basement seems to have vanished. The door is also hinged on the wrong side. (00:12:50)
Hamster

Continuity mistake: When Homer and Bart are at the cabaret show, Mr. Burns and Smithers are there with two women. In almost all of the shots there is a woman sitting between Burns and Smithers, except in the close-up of them when Burns asks "How does he DO it?". Then Smithers is shown as sitting right next to Mr. Burns. (00:21:00)
Twotall
There's No Disgrace Like Home - S1-E4
Continuity mistake: As Homer is carrying the TV towards the pawn shop in the first shot the left window is clear. There is then a tracking shot of the family walking and when they get in front of the store the window has writing on it saying Pawn Shop. The writing is in black and the next shot when they are talking the writing is now dark brown. (00:14:20)
Lummie