Character mistake: When Cartman goes to wrap the chain around the locker room door, there are two signs that read 'Boy's Locker Room', one on the wall pointing to the locker room and one on the locker room door. The sign has been written incorrectly; the word "boys" has been written with an apostrophe after the Y, spelling out the word "boy's." In this context, the word is supposed to be a plural, not a possessive, so the word "boy's" should just be "boys." If it were written as a plural possessive, the sign would read "boys'."
Continuity mistake: When Cartman accidentally sets Fluffy the Cat on fire, it jumps up into the air and knocks over a picture 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. (00:17:45)
Continuity mistake: When Wendy finds her report paper, it has "good effort" and her grade written in red marker pen on it, with a short note underneath it also written in red pen. In the next shot the "good effort" and grade number are still on the paper but the note underneath has vanished.
Other mistake: Cartman says, "What? What happened you guys? Is Kenny okay?" The bandages only covered his eyes, not his ears, so even if he's blinded by his bandages, he still should have been able to hear Stan shouting, "Oh my God! She killed Kenny!" and Kyle's reply "You bastard!"
Continuity mistake: When Stan, Kyle and Kenny are going to Cartman's house to turn him back to normal and get surrounded by the Ginger Kids, Kyle is wearing his pyjamas with a coat over the top. But by the time he and Stan reach the barn to shelter from the attacking Ginger Kids, he's suddenly wearing his normal green trousers.
Continuity mistake: When Kyle slides a $10 bill into the ticket booth, the $10 bill is shown lying left to right. After a couple of cuts to where the ticket taker is saying "But this is such an important film..." the $10 bill has changed positions. (00:03:00)
Factual error: In the flashback of Cartman watching the Ghostbusters remake, there is a list of times for other movies playing at the theatre shown in the ticket booth. The movies listed are The Accountant, Ghostbusters, The Girl on the Train and Kevin Hart: What Now? The flashback is supposed to take place in the summer, around the time the Ghostbusters remake was released. The Ghostbusters remake was released in the US in July 2016, however the movies, The Accountant, The Girl on the Train and Kevin Hart: What Now? were not released in the US until October 2016, almost three months apart from each other.