The Bart Wants What It Wants - S13-E11
Other mistake: Ned Flanders wins the $100 bill, but on the side it says $50.
Weekend at Burnsie's - S13-E16
Other mistake: When Homer gets a promotion from Mr. Burns, the latter's left eye is drawn such that it overlaps his nose. (00:11:30)
Little Girl in the Big Ten - S13-E20
Other mistake: Sherri and Terri are seen participating in the second grade gymnastics (as referred by the gym teacher), even though they're in the fourth grade.
Continuity mistake: This is a mistake for the introduction from seasons 2-20 (1991-2009). When Homer screams, he turns round. You see this in a wide shot. There are no boxes to the right of the door in the garage. However, two just appear out of thin air when he runs through the garage. (00:01:50)
Skinner's Sense of Snow - S12-E8
Nelson: Hey, look how much Skinner makes: $25,000 a year.
Bart: Let's see, he's 40 years old times 25 grand. Whoa, he's a millionaire.
Skinner: I wasn't a principal when I was one.
Nelson: Plus, in the summer, he paints houses.
Milhouse: He's a billionaire.
Skinner: If I were a billionaire, why would I be living with my mother? [All the kids laugh at him.] They're just not responding to logic anymore.
Trivia: The Simpsons holds the record for most guest stars; it is also the only non-variety show to have had appearances from three former Beatles (Paul, George and Ringo).
Who Shot Mr. Burns? (2) - S7-E1
Question: Chief Wiggum says that Space Invaders was an addictive video game, and Groundskeeper Willie says, "Video game?" I don't understand why he is so shocked. Could someone help please?
Answer: The joke is that Willie was so addicted to Space Invaders that he believed it was reality: every time he played, he was actually defending the Earth from dangerous aliens. It's a surprise to him that it was actually a game.
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.