When Mr. Garrison buys a gun, he tries one with a metal stock, but decides to buy the same model with a wood stock. Later, he is carrying the gun with the metal stock.
As Wendy searches through the papers in the classroom, her gloves come on and off.
When Wendy is trying to stop Mr. Garrison, Mr. Hat is sitting on the rifle, but when Mr. Garrison lowers the rifle Mr. Hat is nowhere in sight. Right after Stan asks, "Man, did she really throw her voice with two dummies at once?," Mr. Hat is again on Mr. Garrison's right hand.
At the start when Cartman describes why he hates rainbows, he briefly has yellow gloves on for one close up, then they vanish again.
In the disclaimer at the end of the advert for Weight Gain 4000, "irreversible" is mis-spelt as "irreversable".
During Mr. Garrison's flashback, even as an 8 year old, he still has a mainly bald head with gray hair at the sides, yet in another flashback in "Cartman's Mom is a Dirty Slut," he has a full head of hair like everyone else only 8 years old. His eight-year-old bald look may be the result of wearing a bald cap to enhance the comedic nature of his appearance.
At the beginning when the interviewer asks Matt and Trey why they "keep killing" Kenny, he had only died once in the series.