Thanksgiving - S1-E9
Factual error: The scene where Kitty is making peanut butter celery for Thanksgiving appetizers; she is using Skippy brand peanut butter and the packaging is not from the 70's, it's the current packaging. (00:05:10 - 00:06:05)
The Ninja Poke-Showdown - S1-E32
Factual error: When Venonat uses Stun Spore, Ash tells Bulbasaur to use Whirlwind. Bulbasaur just blows the powder away with his mouth, but he doesn't use the Whirlwind attack. He can't learn Whirlwind in any of the games, and what Whirlwind is supposed to do is to blow the opposing Pokemon away. Ash could have just as easily told Bulbasaur to blow it away, but he instead chose to tell him to use a move that he can't possibly learn. The only Pokemon that can learn Whirlwind are either Flying types or Bug types; i.e., Pokemon with wings (with the exception of Makuhita and Hariyama, which weren't introduced until generation III, and did not exist at the time this episode aired). In The School of Hard Knocks (Season 1, Episode 9), a character mentions information regarding a Pokemon's levels, attacks, and information which is taken straight out of the game, so it's very clear that Bulbasaur should not be able to use Whirlwind. [This is a result of mistranslation. In the original, Japanese version Ash orders Bulbasaur to "blow it away." He didn't say Whirlwind. Still a mistake in the English version.]
A Paige from the Past - S4-E10
Factual error: On the wall of Paige's bedroom when she was a teenager is a Metallica poster for "Garage Inc.", a CD not released until 1998 although Piper later says that Paige has gone back to 1994. (00:16:05)
Factual error: Throughout this episode, when Carrie talks about the functions of the left vs. right sides of the brain, she has them backwards. The right side of the brain is the creative side, the left is the logical one. Apparently, the writers liked the idea that the "right" side of Carrie's brain would ultimately lead her to do the "right" thing about Mr. Big, but that's not the case. Rational decision are made with the brain's left side. (But then again, Carrie never was very rational when it came to Mr. Big.).
Suggested correction: The right and left side being rational/ logical and emotional has been proven wrong. The brain works in a very complex manner and multiple parts on both sides are lit/ functioning when doing either a logical or an emotional task.
Lows in the Mid-Eighties (2) - S3-E9
Factual error: When Will and Grace bump into each other in the supermarket in 1986, more recent items and brand names can been seen in the fridges and on the shelves during the scene.
Kevin Burke's Day Off - S1-E22
Factual error: There is no megatron at Wrigley Field.
Factual error: It is very obvious throughout the whole episode that the mountain scenery is that of California wilderness...the trees, plants and mountains look nothing like those in New York or the East Coast.