
Springfield Connection - S6-E23
Continuity mistake: When Marge sees Homer's car parked illegally over 3 handicapped spots you can see a car parked near Homer's that is orange. Later in the scene when Marge starts writing a ticket up for Homer the car next to Homer's is now a dark brown. (00:14:35 - 00:15:05)
Lummie

Tree House of Horror V - S6-E6
Continuity mistake: In 'Nightmare Cafeteria,' in the opening shot we see Bart standing on a desk in the back row. It cuts to a closeup, and he is now on a desk in the second row from the back, as well as people appearing around him, such as Milhouse, who wasn't even in the classroom in the opening shot. (00:15:25)
Hamster

Tree House of Horror V - S6-E6
Continuity mistake: In 'Nightmare Cafeteria,' when Lunchlady Doris spills food on Jimbo, it only goes onto him. In the next shot it is also all over the table. (00:16:15)
Hamster

Revealing mistake: When Lisa is clapping erasers, you can see the alphabet above the board, and part of the A is cut off.
OL1V3R666
Bart Gets Hit By a Car - S2-E10
Other mistake: When Marge is being questioned, before she says 'If you don't have anything nice to say, then don't say anything at all', there is a shot over her shoulder looking at the blue haired lawyer. Not only is he (the lawyer) there directly in front of her, but he is also sitting on the bench with Burns. In all other shots his chair is empty as it should be.

A Streetcar Named Marge - S4-E2
Continuity mistake: As Marge is about to leave for her first audition, she walks across the room and she is wearing white slip-on shoes. Then her and Homer talk for a bit, then when it cuts to a wider shot after they talk, she now has her red flat-heels on. (00:03:30 - 00:04:00)
Hamster

Team Homer - S7-E12
Continuity mistake: During the classroom scene where Bart reveals his Mad magazine shirt, he removes his sweater and puts it on his desk. In the next shot the sweater disappears. (00:03:40)
Lummie

Continuity mistake: When Otto announces about Milhouse's party, 1, Martin is sitting two seats ahead of Bart and Milhouse, even though he was just talking to them, and 2, Sherri and Terri are nowhere to be seen. (00:01:35 - 00:02:35)
Yoshi
Continuity mistake: When Bart realizes he forgot his permission slip, the camera shows us that the paper is half-under his pillow. However, when he got out of his bed at the very beginning, the paper wasn't under his pillow. (00:01:00 - 00:03:05)
Yoshi
Continuity mistake: At the thanksgiving dinner, Lisa tears one of the legs off of the tofu turkey, but in a later shot the leg is back on the turkey. (00:20:20)
Hamster

Tree House of Horror VI - S7-E6
Continuity mistake: In 'A Nightmare on Evergreen Terrace', when the children are all discussing their dreams, Ralph's sling is blue. After the shot of Principal Skinner, Ralph's sling is white.

Tree House of Horror V - S6-E6
Continuity mistake: In 'Nightmare Cafeteria,' Lisa and Bart run into the basement, to tell Marge they are cooking kids at school. Between shots Bart and Lisa swap places. (00:18:15)
Hamster

Homer Badman - S6-E9
Continuity mistake: When Homer mixes the Pop Rox with the soda he leaves the Pop Rox packaging over the can. After he throws the can and we see it in the air the Pop Rox packaging has disappeared.
Lummie

Lisa on Ice - S6-E8
Other mistake: As Homer is signing Bart's academic alert form just before Marge starts talking to Lisa you can read the writing below the "Academic Alert" title, but the writing is completely incoherent including sentences such as "IMAEGTSIAD TSNHOJI NAMREB". Update; some of the "words" or parts of them are people's names, such as David, Stuart and Allison, but backwards. (00:03:50)
Lummie

Radio Bart - S3-E13
Continuity mistake: When Rod and Todd talks to 'God' on the radio, the antenna keeps changing position for the entire scene. (00:08:50 - 00:09:40)
Yoshi
Tree House of Horror VII - S8-E1
Continuity mistake: In 'The Thing and I' Dr. Hibbert is about to explain Bart's irregular birth. In the closeup before the story, Dr. Hibbert has a stethoscope around his neck. This wasn't there in previous shots. (00:03:50)
Hamster

Homer Badman - S6-E9
Continuity mistake: After Marge's left pocket rips in the candy convention, she goes to start picking up the candy when we see that the right pocket has ripped all of a sudden. When Homer and Marge start running away the pockets are no longer ripped and full of candy again.
Lummie

Springfield Connection - S6-E23
Continuity mistake: Before Marge sees Homer parking violation, if you look at where he is parked over the first handicapped spot there is a car parked in the first non-handicapped spot. A bit before Marge arrests him there is now a non-handicapped spot between the car and Homer's car. (00:14:35 - 00:15:05)
Lummie

$pringfield (or How I Learned to Stop Worrying and Love Legalized Gambling) - S5-E10
Continuity mistake: When Homer makes the food with the mix of Tom Collins mix, cloves and a pie crust you can see the labels on the Tom Collins mix and the cloves change between mixing the ingredients and after tasting them. Also the top on the Cloves bottle keeps changing through the scene. When Homer takes the bottle out of the fridge you can see a red top on it. When he sits down the top has disappeared and starts pouring the cloves. When the shot changes the red top is back and it disappears after that. (00:15:20)
Lummie
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.