Corrected entry: The towel Flanders wraps around Apu's head changes shape between when it is first applied, and when the customs agent sees Apu. First it is an almost perfectly round shape with no loose ends, then it becomes a more flat shape with a loose end hanging over Apu's shoulder. When Apu is seen inside the police van, the towel is once again in the original shape.
Corrected entry: It takes two years for Marge's kitchen to be finished, but Bart and Milhouse are still planning their Playdude treehouse as if no time has passed at all. Surely in two years they would have either lost interest or finished making the Playdude treehouse? It only takes them a few weeks to get it up and running once the kitchen is finished.
Corrected entry: In this episode Apu says in the car on the way to Canada that he worships several gods. But in a much earlier episode, "Homer's Barbershop Quartet" during a flashback when Apu is asked to change his name he says "It is a great dishonour to my ancestors and my god."