Everything in Its Right Place - S4-E11
Character mistake: Lucas is seen placing flowers on Keith's tombstone, which states he died on January 23, 2006. In the next shot Lucas places a single flower on the grave of Jimmy Edwards, who died the same day and in the same scene as Keith, yet his tombstone states that he died on March 1, 2006.
Character mistake: In the map of South America, the nation of Chile is misspelled as "CHLIE." (00:18:05)
The Purple Panther: Part 1 - S3-E6
Character mistake: In the song 'The World Goes Round', Stingy sings about dinosaur bones from the Stone Age (the second verse). The dinosaurs were wiped out about 65 million years ago while the Stone Age started 2.5 million years ago, an obvious time gap.
The Madness of King Bob - S4-E9
Character mistake: Whenever the Hustler Kid delivers Randall's prize in the beginning, he says, "Grand prize delivery for Mr. Randall C. Weemes." But Randall's middle initial is J.