Chin Up! / Dog's Day Afternoon! - S1-E5
Deliberate mistake: When Cleft (Timmy) and the Chin go to the last page with the letters and they get to Timmy's letter, Chin says he spelled Chin wrong yet you must see it's spelled right.
The Fairly OddParents (2001)
1 deliberate mistake in season 1 - chronological order
Starring: Tara Strong, Carlos Alazraqui, Daran Norris, Susanne Blakeslee
Father Time! / Apartnership! - S1-E4
Plot hole: Timmy uses his heat vision, that he previously wished for, to win the race for his future dad. But it's revealed later in "Smarty Pants" that if you use a previous wish in a contest, it is magically taken away because it's cheating.
Upvote valid corrections to help move entries into the corrections section.
Suggested correction: That is true, that rule was mentioned in a later episode. However in the episode Christmas Every Day, it was revealed that new rules could be added at anytime. So it's possible that the rule simply didn't exist yet. Although, this plot hole may apply to any episode released after "Smarty Pants."
Wandisimo: Principles, much like my biceps, are muy bonito.
The Big Problem! / Power Mad! - S1-E1
Trivia: In the episode "Power Mad", when Timmy, Chester, and AJ enter the video game, their outfits are almost identical to the virtual outfits in the movie "Tron".
Engine Blocked / Mighty Mom and Dyno Dad Meet the Crimson Chin - S3-E5
Question: Do you think it depends to use your left or right foot for the pedals? Or is there a fixed rule to use either foot? (The accelerator pedal is shaped like a left foot.).
Answer: That's just decorative. The gas pedal is always on the right and using the left foot would be quite awkward.