Character mistake: When Lisa is taken to the hospital, she tells Kathy that she saw the ghost of Jodie DeFeo. The name of both of the DeFeo's daughters wasn't Jodie. Their names were Dawn and Allison. Jodie was the name of a demonic pig that the Lutz's daughter Missy had befriended.
Suggested correction: While this is true in the original novel, the writers chose to change it to the DeFeo's daughter's name in the movie. Creative license doesn't count as a mistake.
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: After the Lieutenant is shot and is in hospital, his CO is explaining what the GHOST system is. He explains that the acronym is "Guided High Altitude Scrambling Transmitter" - which would be GHAST. Replacing "altitude" for "orbit", which is probably what was intended, would make a Guided High Orbit Scrambling Transmitter - or the GHOST system henceforth referred to in the film. (00:06:25)
Character mistake: When Lt Gannon is in the dogfight with the Russian jets, he announces that he is deploying "chafe and flares." The term is spelled and pronounced "chaff", and any pilot would know that.
Character mistake: When the plane is speeding down the runway at the beginning, a female flight attendant is seen walking, and Kyle is seen buckling her seat belt. Everyone would have been sitting down and buckled in at this point.
Character mistake: When the Smiths first enter the store Home Made, the camera pans around and faces the store's large display picture which reads, "The true measure of a home lies in it's kitchen," but the word "it's" should be "its."
Character mistake: In the beginning of the movie, Simon Broome and Xola speak in English and Xola acts as the only speaker of Ku. He confirms to Simon that the three young boys are Ku but if Simon grew up as a Matoban like Silvie, he would have been fluent in Ku as well.
Character mistake: When the main character follows the Dutch businessman down the stairs (the same scene the girl with the white jacket and white bag walks downstairs before we see her walking up the stairs) there is a commercial which reads "JETZT AUCH AM DVD" which is wrong and should be "JETZT AUCH AUF DVD." (01:22:45)
Character mistake: The bad guys at the beginning of the movie launch a drone that scans for target. The woman's data appears in the HUD and it says "Stacey Canon - Interpol REGISRTY" (00:02:20)
Character mistake: When the plane is landing, and we see out the window that landing is less than 10 seconds away, the captain says: "Cabin crew take your seats." By that point they should have been seated for a long time.