The inside handle of the bathroom door changes to a doorknob.
In the cafeteria with helga and Stinky, there's a severe case of reusing character designs. A boy sitting at the table behind Helga, is also shown at a table behind Stinky as well. And when Stinky asks for a Mr. Nutty Candybar, we see Stinky's design is used for a boy sitting at another table, on the right-hand side, making it appear there's two Stinkys.
When Stinky tells Helga that he doesn't know how to skate, Gerald is seen skating with Nadine. However, he is seen seconds showing up with Arnold.
At the skating rink, Curly's glasses can be seen changed into Phoebe's glasses.
