Continuity mistake: When Mr. Burns tells Smithers that Homer is the next employee of the month, his huge red chair he was just sitting in has disappeared, and Mr. Burns is in a different position. (00:10:30)
Continuity mistake: When Homer apologizes to Moe at the end, he comes in while the door is left open. It remains closed for the rest of the scene. (00:21:05)
Continuity mistake: After the dinner with Sideshow Bob, Patty, Selma and the Simpsons, the food on Bart's plate changes between shots. We first see a piece of meat with some peas, then we see two pieces of meat and some mashed potato. It changes randomly throughout the scene. (00:02:40 - 00:07:05)
Tree House of Horror II: A Simpsons Halloween - S3-E7
Continuity mistake: When Homer purchases the monkey's paw, you can see open desert to the right of Homer. There was a building in its place a few shots earlier. (00:02:30 - 00:03:15)
Continuity mistake: At Li'l Ludwig's Music School, when Lisa plays her sax she has a rope around her neck, attached to the sax. Then when Lisa yells "You're wrong. You're wrong." The rope has vanished, but is around her neck in the following closeup. (00:05:05)
Continuity mistake: When Bart writes the first letter as Woodrow, he writes it on lined paper. However the letter Edna reads is on plain paper. (00:07:30)
Burns Verkaufen der Kraftwerk - S3-E11
Continuity mistake: When Lenny tells Homer he's the safety inspector, the donut and paper cup have disappeared from his hands. (00:10:05)
Continuity mistake: In the scene where Miss Hoover asks Lisa what the ninteenth-century figure nicknamed 'Old Hickory' is, there is no text on the covers of the book she's holding. In the next two shots, however, 'Teacher's Edition' can be seen on The Front cover and the spine of the book. (00:17:00)
Audio problem: When Michael and Bart are playing a song to Lisa, Bart uses her bin as a drum. Sometimes you hear tapping, but Bart doesn't touch the bin.
Continuity mistake: When the family are driving home from the cinema, Bart draws an angry face on the back of Homer's head. It is never there at any other point in that night.
Continuity mistake: Near the beginning when the family is eating dinner, the glasses on the table keep refilling/emptying themselves, even though nobody takes a drink. (00:03:40 - 00:04:30)
Bart's Friend Falls in Love - S3-E23
Continuity mistake: When Lisa is explaining about subliminal tapes to Homer, there is a robot on the cover of the magazine, whose helmet is yellow. But in other parts of the episode, it is grey.
Continuity mistake: In the video store, when Homer looks at sports tapes, the categories of movies behind him change from drama, horror, and 'Elvis' to drama, western and horror. (00:05:55)
Continuity mistake: At the beginning, if you watch the clock as Homer walks in, the time changes between shots. (00:01:30)
Audio problem: When the old lady is playing the keyboard at Homer and Marge's wedding, her hands don't match the music.
Revealing mistake: On the original DVD version, when Bart says to Lisa "I didn't want you to wreck your life" the screen is cut off on the right side slightly. (00:20:25)
Continuity mistake: The card Bart has written for Milhouse is blank inside. However when Lisa looks at the card, the pun of the joke (on The Front of the card) is now there. (00:01:15)
Lisa's Pony - S3-E8
Other mistake: When Lisa rings Homer to tell him that she loves him, the shot of her talking is re-used from "Bart's Dog Gets an F." We can tell this because her cheeks inexplicably appear puffed up (in "Bart's Dog Gets an F" she had mumps).
Lisa's Pony - S3-E8
Continuity mistake: The number of knives that Sherri is holding changes between long and close shots at the talent show. (00:04:50)
Burns Verkaufen der Kraftwerk - S3-E11
Continuity mistake: When Homer is at the vending machine, in certain shots he is wearing a tie and in others he isn't. (00:02:20)
