Continuity mistake: When, Lisa bangs on the window of the operating theatre, there is a person sitting behind her who is asleep. However, when she shouts to Dr Nick, the people behind her are completely different. Then she sits down again, and the sleeping person is behind her.
Continuity mistake: When Homer and Bart are escaping from the cops after stealing kegs of beer from the dump, they drive through a cemetery and slam into a headstone, breaking the right headlight of the car. When they pull into the driveway back at Evergreen Terrace, the left headlight is the broken one.
Continuity mistake: As the Simpsons are in the cinema watching "Kosovo Autumn" you can see there is a seat next to Homer to the right of screen. When Homer starts complaining about the film but cannot leave because he is stuck in his seat, the shot changes and we see him from behind however the seat that was next to him has disappeared.
Continuity mistake: As Homer is giving his speech to the dressed up monkeys, all of the monkeys are dressed in blue suits and you can also see there is one monkey next to the stairs on the stage. In the next shot of Homer leaving the stage there is now six monkeys, with only one wearing a suit and it is grey.
Continuity mistake: When we first see Willie standing by the Black Wall of field trips, the latest entry is at Willie's eye level. But when the angle changes, there are a lot more names on the wall, making the last entry appear just by Willie's chest.
Continuity mistake: The stocks that are put on Marge and Homer are fitted so that their head and hands are secured and cannot be removed. Whilst in Flanders garage and Homer is using the rotary saw to remove Marge's stock, Homer's stock is still secured on him but his arms and shoulders are through the stocks.