Character mistake: When Stuart calls home from the pay phone he's talking into the wrong end of the phone.
Character mistake: One of the other trainers said he rode over on a Pidgeotto, but it was a Pidgeot. (00:40:07)
Character mistake: In the scene where Steve and Josie prepare to leave to fight the giant robot at the beginning of the movie, Steve tells Will "Oh, Will, a reminder: a lot of the kids at Sky High will only have one super hero parent, not two." When he says "one super hero parent", he holds up two fingers. When he says "not two", he holds up only one finger.
Character mistake: When Greg reads the article about L'il Cutie being cancelled, cartoonist is misspelled cartoonish. The article also repeats the first column word for word in the third column.
Character mistake: When Wood is telling Harry the rules of Quidditch he says that if you catch the Snitch the game is over, which is true. But then he also says that which ever seeker catches the snitch, their team wins, but that isn't true. Granted that the 150 extra points probably would give you the winning lead, but as JKR pointed out in the 4th book at the Quidditch World Cup, you can catch the Snitch but lose the match. And you'd think explaining the rules to a first-timer you would want to get it right. (01:05:40)
Character mistake: When Kevin is shooting the toys off the laundry chute with Buzz's BB gun, he's looking through the scope with his closed eye.
Character mistake: When Stan inflates himself, Michael asks, "How'd he do that?", implying that he doesn't know the rules of the Looney Tunes world. Since Michael was rolled into a ball by the aliens earlier in the film, this shouldn't be too much of a surprise.
Character mistake: When Jimmy explains to the kids of the town where the aliens took their parents, he mentions the origin of the aliens being somewhere in the Orion Star System, 3 million light years away. The Orion system is way closer than that. It is actually less than 1400 light years away from Earth. 3 million light years away would place them further than the Andromeda Galaxy.
Character mistake: In the film, five items are stolen: the Magna Carta, the Turin Shroud, the Imperial Sword of Japan, the Pope's ring and the Pink Panther diamond. When Alfred Molina's character is challenged that they had found everything but the Pink Panther, he protests that 3 out of 4 is not bad, that's 75%. In fact, they had found 4 out of 5 or 80%.
Character mistake: Chad actually steps on first base before the baseman has the ball. He was safe.
Character mistake: Before the Megarace, Rez looks back at the camera and says that they'll try to help him out-but you can see Juni's tires in front of Rez's car. In a shot before this one, Rez says Arnold will crush Juni-looking at the camera, which is in front of Rez.
Character mistake: When Casey is using her knowledge of physics to advise a figure skater, she states, "Pull your arms in real tight. That increases your moment of inertia". In fact, this is the exact opposite of how it really works. Reducing her overall radius makes her rotational inertia smaller. (00:21:05)
Character mistake: When Arthur Weasley takes Harry aside in The Leaky Cauldron to warn him about Sirius Black, he says, "13 years ago, when you stopped.... You-Know-Who...Black lost everything." Harry is 13 yrs. old in Prisoner of Azkaban and was a 1 yr. old when he stopped Voldemort. Hence, Harry stopped Voldemort 12 yrs. ago, and not 13! Harry turns 11 just before school starts in Philosopher's Stone, turns 12 before school in Chamber of Secrets and turns 13 yrs. old before school in Prisoner of Azkaban. Just an aside, the last digit of Harry's age always coincides with Harry's year at Hogwarts. So, he's 13 in his 3rd year at Hogwarts, which is entitled Prisoner of Azkaban. (00:17:50)
Character mistake: When Chessy confronts "Annie" when she's presenting her with the big breakfast, she's talking about when Annie was on the phone the night before. Then she says her father overslept, when she actually meant to say and "and you overslept," as the conversation doesn't make any sense saying that the father overslept. (00:58:00)
Character mistake: In the scene where the photos of Daphne are flashing by, you see her in a photograph which was supposedly taken at the Chelsea Charity Auction. In the caption, "auction" is incorrectly spelled "aution."