Audio problem: During Selma and Bob's conversation at the dinner table in the Simpsons' house, Bob says "Although kissing you would be like kissing a divine ashtray." His lips don't move when he says "although".
Continuity mistake: When Marge is talking to Lisa in her room about Band Practice, Lisa is reading comics, eating potato chips, and there is a drink by her as well. The drink container starts out green with a light purple label, then goes to being grey with a red label then as Marge tells her story, the colours of the drink change again twice. (00:10:00 - 00:10:55)
Continuity mistake: Marge tells Bart not feed Maggie the Monopoly houses. Bart shows the box and says that there's enough of them. The shot later, the box has disappeared. (00:16:15)
Burns Verkaufen der Kraftwerk - S3-E11
Continuity mistake: When Carl complains that he can't be fired, everybody behind him, Homer and Lenny has disappeared. (00:09:00)
Burns Verkaufen der Kraftwerk - S3-E11
Continuity mistake: As Horst and the guy talks to Homer, the guy is holding a folder in the first shot, then it suddenly disappears, before appearing on the desk without him putting it there. (00:12:45)
Lisa's Pony - S3-E8
Continuity mistake: When Lisa calls Homer at work, Homer picks up the phone on his left side. Instantly after, we see him hang the phone up on his right side. (00:19:00)
Tree House of Horror II: A Simpsons Halloween - S3-E7
Continuity mistake: After Lisa declares world peace, when the two UN guys hug each other, the United Nations symbol on the wall has changed from purple to blue. (00:05:25)
Tree House of Horror II: A Simpsons Halloween - S3-E7
Continuity mistake: When Homer picks up the monkey's paw for the first time, a person walks behind him. He has disappeared in the next shot. (00:02:35)
Continuity mistake: When Homer tells Carl and Lenny about the movie they watched, they change positions, and there is much more on the table. (00:03:35)
Other mistake: When the wheel falls off Bart's skateboard, in the shot where he curves left sharply, you don't see the school in the background. How could he be at the social club if he just left school? (00:05:20)
Continuity mistake: Bart's drawing of Principal Skinner is gone when Mrs. Krabappel says that he is missing. (00:14:05)
Revealing mistake: If you look carefully in Mr. Burns' surveillance cameras, the workers are identical. (00:02:50)
Bart's Friend Falls in Love - S3-E23
Revealing mistake: When Bart tells Otto not to leave due to Milhouse not being on the bus, when Otto replies you can see that his left arm up to the headphone cable flashes pink for a frame. (00:07:45)
Bart's Friend Falls in Love - S3-E23
Continuity mistake: When Samantha is introduced to Bart's class, to Wendell's right and a boy sitting in front of him there is an empty column of desks. But in the overhead shot, this column has disappeared. (00:04:45)
Continuity mistake: When Marge's sisters start smoking in the flashback, there is only one ledge on the wall behind them. In the next shot there are three ledges and a clock. (00:04:05)
Burns Verkaufen der Kraftwerk - S3-E11
Continuity mistake: Homer drives his normal car to the plant's parking lot. When he and Carl meet, his car has changed to being blue. (00:07:00)
Other mistake: When Bart and Homer do a test drive on their race car, it is daytime, when supposed to be night-time. (00:11:50)
Lisa's Pony - S3-E8
Continuity mistake: During Lisa's performance, In one shot of the audience we see, from left to right: Ned Flanders, Maude Flanders and some lady. The rest of the talent show showed us that Jasper was sitting where the lady was. (00:05:45)
Continuity mistake: When we see Skinner's car before the newspapers fall on him, it is a light-brownish color. When the police arrive, it is the same color as the cop cars. (00:19:10)
Continuity mistake: At the beginning of the episode, the school is a light purple colour, yet near the middle of the episode, the school turns yellow. (00:00:50 - 00:12:20)