Simpsons Already Did It - S6-E7
Character mistake: Butters says that he watched "all 132 episodes" of the Simpsons; at the time this episode aired, 291 episodes of the Simpsons had been produced and aired.
Continuity mistake: When Mr. Garrison is carrying around his gun, it is not the wood finished gun with the wood colored hand grip that he bought, it was the other one that had the grey hand grip. (00:14:20)
Suggested correction: He says he will have it (wood finish) then it shows him walking through town. Plenty of time for him to change his mind again.
Perhaps, but later when Stan and Wendy interrupt him, his gun exhibits wood furniture again. Unless he purchased both, some error has been made here.
Coon vs. Coon and Friends - S14-E13
Deliberate mistake: S14 Ep13 Coon vs. Coon & Friends: in the South Park universe, Canadians are depicted as looking the same (beady eyes, stick legs, heads sliced in half). Since Justin Bieber is Canadian, he should look similar to Terrance and Philip instead of having a normal face and body.
Suggested correction: I don't see how this is a mistake, deliberate or otherwise. While the creators of the show have established that to be the appearance for Canadian characters, they are well within their rights to invoke artistic license whenever they see fit. Is it also a mistake that Mel Gibson and Saddam Hussein have photorealistic faces when the majority of other characters have been established as having cartoon faces?
Korn's Groovy Pirate Ghost Mystery - S3-E10
Character mistake: Cartman tells his mother that there are only 72 shopping days left until Christmas. Christmas is 55 days after Halloween.
Suggested correction: Butters is always shown as being a bit dim and slow. As a kid it's easy for him to make a mistake in thinking that there was only 132 episodes.
Ssiscool ★
That's why it's called a "character mistake"; also, Butters is certainly naive, but he's hardly what I would call "dim and slow."
zendaddy621