Continuity mistake: Helga makes Arnold sit in a plate of chocolate pudding as a prank, leaving a huge chocolate pudding stain on the back of his shirt. Then, when Arnold picks up the gift box from Grandpa and returns to the cafeteria, the chocolate pudding is gone from his shirt but reappears later on when Arnold and Helga are at Slausen's Ice Cream. (00:12:37)

Hey Arnold! (1996)
1 continuity mistake in April Fool's Day - chronological order

Weird Cousin / Baby Oskar - S4-E11
Other mistake: Stephen Viksten is credited twice for voicing Oskar.
Downtown as Fruits / Eugene's Bike - S1-E1
Trivia: Eugene's bike has a "YOOJ" (pronounced like "Eugene" without the "een") license plate.
Question: Does anybody know what year this show takes place? I've noticed that there are all these present day video games, keyboards, etc. on the show, but all the cars are old fashioned.





Answer: The show is based in present day times. Plus most cars aren't old fashtioned, I recall seeing a limo and not to mention a cherry picker, etc.