Plot hole: After District 5 become the Ducks, they have a bunch of fans attending their games from there on out. Problem is, they have fans that show up out of nowhere and also said fans have team merchandise already (sweatshirts, hats, flags, etc). It's also rare for pee-wee hockey teams to even have team merchandise unless they are a long-running franchise.
Plot hole: While we never see Lisa leave the courtroom at the end to call Judge Malloy to send the fax verifying Jerry Callo, it is possible she snuck away for a minute to do it after the dismissal and before they leave the town. However, Vinnie does not ever seem to mention that he told the judge he is Callo to her so how did she know? He must have mentioned it to her while they were rushing to leave, they were back on speaking terms and she called Malloy.
Plot hole: After Captain Ron gets fired, Martin mentions seeing Roscoe. How does he know who this person is? This is the first time we've heard Roscoe mentioned in the film. Sure we are then shown that Roscoe is the pimp for the prostitute but how did Martin know who he was?
Suggested correction: A couple of minutes before Roscoe give Martin a nasty look as Martin shoves by him. Martin looked back at him so he has seen him before.
Plot hole: The Frying Dragon team wins the Breaking, Weapons, and Men's Fighting competitions, as well as coming in second place in the Women's Kata, yet they are still only tied for the lead in the end?
Plot hole: How is it that the Flying Elvis' have an extra parachute on board for Jack?
Plot hole: At the climax of the movie, the bully reveals Link to be a caveman by among other things, breaking into the High School and stealing his student registration papers, containing among other refuse, the vaccination license of a dog. Problem is, wouldn't the school staff have already checked those at the start of Link's time as a student?