Magic Show / 24 Hours to Live - S1-E18
Audio problem: Helga rides past Arnold in a bus and yells "24 hours until you die!" or something like that. Her mouth never moves- it just stays open in an evil smile.
Suggested correction: Although it's hard to make out, her mouth is moving when she says that. Also, she says "23 hours until you die!" not 24.
Magic Show / 24 Hours to Live - S1-E18
Continuity mistake: The boarding house has a downstairs bathroom, but in "Gerald Comes Over", there's only one bathroom and it's upstairs.
Magic Show / 24 Hours to Live - S1-E18
Audio problem: Magic Show: During Arnold's magic show, the kids start chanting, "Make Helga disappear!" When Helga says, "Alright you bunch of clods," they stop, but their voices can still briefly be heard. (00:03:28)