Corrected entry: After the episodes "Cartman's mom is a dirty slut" and "Cartman's mom is still a dirty slut," in which we find out that Cartman's mom is actually his father and his mother is yet to be found, Cartman's mom is still always mentioned as Cartman's mom even when the kids say Cartman has no mom, and also they say he has no dad.
Correction: They call her "Cartman's mom" out of habit.
Corrected entry: For maybe the first four seasons, Stand and Kyle's voices stayed the same, after season four though, they seemed to have gotten deeper. Couldn't have been because of puberty because if that was the case Cartman's voice would have changed also.
Correction: Obviously you are not aware of the fact that many guys can experience puberty and deeper voices at a later age than others. Aside from that fact, this mistake is more built on opinion rather than any fact. I have watched South Park for many years and there is no example to prove this observation.
Corrected entry: In the school classroom the alphabet above the chalkboard is all screwed up with the alphabet in capitals being normal but the lower case letters are all jumbled up.
Correction: Yes, that's true, but it is an ongoing joke. How can the kids learn if even the alphabet is all screwed up? As Stan said himself, "We just fake it to shut him up."
Corrected entry: Chef is never shown from his side. He's either facing the camera or facing directly away from it, even when he's walking across the screen, not turning 90 degrees like other characters.
Correction: Chef is shown walking side on in the episode Cartman Gets an Anal Probe (series 1). For what it's worth, I first read this trivia entry yesterday and thought "Hey, that's right." Then last night I just happened to see Cartman Gets an Anal Probe on TV and there it was.
Corrected entry: In the first episode "Cartman Gets an Anal Probe" Stan throws up whenever Wendy tries to talk to him. He also throws up at gore during "South Park Bigger, Longer and Uncut". But he rarely pukes at gore or when Wendy speaks to him in other episodes.
Correction: This isn't a goof, its just the characters' personalities and behavior changing. Its no different from Cartman's voice being different in the 9th season as compared to the 1st season.
Corrected entry: Cut-out characters frequently cast shadows on the background where they shouldn't. A good example is during "Weight Gain 4000" - when Mr Garrison is talking to officer Barbrady, he casts a shadow on the sky. This is very noticeable in almost every episode.
Correction: This isn't a mistake, its part of the gag of the show: the incredibly simplistic animated style isn't intended to be photorealistic. Incidentally, the only episode of the show that is cut-outs is "Cartman Gets an Anal Probe." Every subsequent episode is animated via computer software.
Corrected entry: The American flag in front of the school has an incorrect star formation.
Correction: Almost certainly intentional.
Correction: Cartman has known Liane as his mother for his entire life, and his friends always knew her as Cartman's mom. When people find out that someone was not their biological parent, they often consider the person to still be their parent. And nobody has properly filled the role of a father for Cartman. So, despite knowing that Liane is biologically his father, he continues to feel that she is his mother and he has no father.