Full Moon / Student Teacher - S4-E1
Revealing mistake: Student Teacher: When Olga says, "But, nothing, baby sister!" before giving Helga detention, Rhonda and Brainy disappear for one frame. (00:17:17)
Blue Wants to Play a Song Game - S1-E14
Revealing mistake: After Blue and Steve play the monkeys jumping on the bed game with the sock monkey, when the mail time song plays Steve gets up excitedly and his arm and hand get cut off.
