When Timmy is always right based on what he says, after Cosmo and Wanda disappear (because he told Crocker he didn't have godparents), the wish still worked with Vicky's life savings being roasted, Francis' bee stings and school ending early. However, Timmy was wrong when he said that Vicky nor AJ would not listen to him if tells them that he has fairy godparents.
When Mr. Crocker asks Timmy (who's always right in this story) how many stars are on the US flag, Timmy answers, "49". (News of North and South Dakota reconciling and merging comes over the PA.) The flag in the classroom, which had had 16 stars on it (in a 4x4 pattern), then loses one of the stars. (This spoofs the animation style of this cartoon, where details like the numbers of fingers on characters' hands, details on flags, etc., are often overlooked.)