The Simpsons Movie (2007)

Continuity mistake: During Homer's attempt at rescuing his family, when the EPA truck stops at the fake stop sign, in the wide shot the truck's visors are up and there's no rearview mirror, but in the next close-up both visors are down and a rearview mirror has appeared.

Super Grover ★

Homer: I'll teach you to laugh at something that's funny!

Trivia: As inspiration for the crowd scene in the film, the production staff spent a long time looking at the Simpsons poster that features over 320 of the show's characters. Groening said that they did try to put every single character into the film, with 98 having speaking parts.

Ictoabu

Question: When Homer opens the curtains from the Red Rash Inn Motel room, there are several Advertising sign posters in foreign languages. The one in the middle-right is in Korean and it advertises classes to learn English with a Texan accent. Can someone explain what this joke is about?