Continuity mistake: In the beginning, Bart's bedroom's window faces the backyard. When the bus leaves, it faces Evergreen Terrace. At the beginning of Bart's nightmare, it faces the backyard again. (00:00:55 - 00:15:45)
Other mistake: When Bart sees that Santa's Little Helper ate his homework, and the camera moves really fast, you can see that the Krusty Doll and picture frame have vanished from the desk beside his bed. (00:00:55 - 00:01:50)
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)
Continuity mistake: When Bart finds out that Homer took the police badge out of the cereal box, it changes from brown to pink. The food inside the box also changes to pink. (00:01:10)
Continuity mistake: At the beginning, if you watch the clock as Homer walks in, the time changes between shots. (00:01:30)
Continuity mistake: In the beginning, when Bart finds that the dog ate his homework, the poster on Bart's door has disappeared for one shot. (00:01:45)
Revealing mistake: When Bart is hanging from the play bars his hand goes through the bars. (00:02:35)
Continuity mistake: Bart's bruised eye has healed by the time he reaches Skinner's office to lick envelopes. (00:02:40)
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: When Bart crashes at the door of the Legitimate Businessman's Social Club, his head is facing the door. You can only see this for several frames. In the next shot, his head is facing the sky. (00:05:25)
Continuity mistake: When Bart crashes at the social club, his skateboard changes position between shots. (00:05:30)
Continuity mistake: When Bart falls in the entranceway, a puddle appears under his head between shots. (00:05:30)
Continuity mistake: Bart clears some dust off the picture of the Manhattan, once he's made the drink a few seconds later all the dust has gone. (00:06:40)
Continuity mistake: The drink above the Manhattan on the board changes name and picture. (00:06:40)
Continuity mistake: When Bart arrives home after his bad day, he is seen wearing his lucky red hat. It was never visible anywhere before he got home. (00:07:10)
Continuity mistake: Bart puts his lucky red hat on the hat holder. It disappears in the next shot. (00:07:10)
Continuity mistake: During the Itchy and Scratchy cartoon, things change about the positions of the cats, the clothing, etc. (00:07:55)
Continuity mistake: After Itchy and Scratchy we see Bart and the mob sat in the bar, the mobster at the end of the bar has his drink in 1 hand or 2 hands depending on the shot. (00:08:16)
Continuity mistake: When Homer is gambling with the gangsters, you can just barely see the shoulder of an ORANGE shirt that Bart is wearing, but in all other shots he is wearing his tuxedo. (00:12:10)
Continuity mistake: When the mobsters enter Skinner's office, the phone on his desk changes position between shots. Also, the name bar on his desk doesn't read anything on it. (00:13:50)
