Continuity mistake: In the classroom scene where Kyle tries to be excused from class to find Ike, Cartman sets Pip on fire as he was sitting just behind him to the the left. However in the previous shots Pip had not been sitting there, some other kid was and wouldn't have had enough time between shots to move.
Continuity mistake: Cartman accidentally sets Fluffy the Cat on fire. When the cat is on fire, he jumps up into the air and knocks off the picture on top of the cabinet and it falls onto the floor. When Stan, Kyle, Cartman's mom and Wendy walk into the living room in the next shot, the picture has disappeared.