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.
Character mistake: Ben Stein asks a chemistry question about -273° Kelvin. The problem is, the scientific community never uses the word 'degrees' when referring to Kelvin. The correct way to say it would have been, "-273 Kelvin is also known as what?" Also Kelvin cannot be negative since 0 kelvin (approx -273° Celsius) is absolute zero.
Character mistake: When Mikey looks at the Picture Day schedule, he points out that 4th grade is going last. However, the schedule says they are after 3rd grade and before 5th grade, actually making them fifth. The faculty is actually listed last on the schedule.
Magical Express Murder Case: File 3 - S2-E12
Character mistake: In Akechi's flashback, the board with the flight for Los Angeles has accurate names of airline companies (they seem to have swapped "Virgin" with "Kristen", for some reason) but the flights for Seoul is from "KSREAN" Air, clear misspelling of "Korean." (00:14:15)
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