Continuity mistake: Gamble and Hoitz get thrown to the ground when the accounting office explodes. In an overhead shot of them rolling around on the ground, Gamble's wooden gun has fallen from its holster and is lying on the ground. Cut to a side shot and the gun is back in its holster. Gamble had both hands covering his ears the whole time, he did not pick up the gun. Then comes another overhead shot, the wooden gun is again missing from the holster.
Continuity mistake: When Jessica appears on stage, Eddie has Betty Boop standing next to him in all close-up shots, except for a wide shot of the public behind Jessica where Boop is missing. (00:18:15 - 00:19:05)
Continuity mistake: When Carter and Zhang Ziyi are fighting, Carter is wearing alligator skin shoes (brown). However, when Ziyi thrusts the sword at Carter and Carter falls back on a chair raising his feet, you see him wearing black running shoes with a white sole.
Continuity mistake: In their first night at the new house the Beardsley's lose power completely. When the doctor arrives (Tom Bosley) he rings the electric doorbell.
Plot hole: When they are being told they have failed the evaluation, the dean tells them, "Yes, you people did finish with 84%, but another one of your pledges finished with a zero in every category." It then goes on to state that this drops them down to 58%. For one pledge to bring them down 26% there would have to have been less than four pledges, including Blue, i.e. only three actually taking the evaluation.
Continuity mistake: When Troy is in the locker room with his teammates, Chad is handed the framed photo of Troy's father and there's a white sticker on the back of the frame. In the next shot, when Chad gives the frame to Troy, the sticker is gone. (00:58:50)
Continuity mistake: Truly crashes into the pond three times: first when the kids are playing in the road and she takes them home, second on the day of the picnic when she says she has nothing else to do and will go on the picnic too, and third at the end of the film when Potts finds out he is rich. In the second of these three, when Mr. Potts carries Truly from her car in the pond, the end of the ribbons on the back of her dress gets soaked in mud, but when you see her again at the beach there is no sign of the dirt.
Continuity mistake: In the final chase scene, the yellow Hummer starts out with an open sunroof. As it barrels through the shantytown, interior shots of the Hummer show it with a large overhead bank of storage compartments, while overhead shots show the sunroof. When the chase finally reaches Gitmo, the Hummer once again is shown with an open sunroof. (02:11:50 - 02:12:55)
Other mistake: Dr Anne wets her dress by dropping water on it, but her dress is dry afterwards. (00:54:00 - 00:55:30)
Revealing mistake: When Tim Allen startles Santa Clause and he falls off of the roof, Santa's foot kicks up a blanket that was used to look like some snow on the roof. (00:14:10)
Factual error: All the Cisco VoIP phones seen in the film have the booting Cisco logo on them and would not work due to no connection.
Factual error: The main character from the video game "Paperboy" is among the alien invaders in the final battle; since that game was first released in 1984, he shouldn't be there, because the probe the aliens received featuring video game footage was launched into space in 1982.
Continuity mistake: When Terri is at the party, her blonde wig changes shape and size many times.
Continuity mistake: At the end of National Treasure 1, Riley has a Ferrari 360 Spider. At the beginning of Book of Secrets, when his car is being towed away, it's a Ferrari F430 Spider. At the end of the movie, he is given back a 360 Spider.
Visible crew/equipment: In one scene Ace is drumming large mushrooms supposedly growing on the side of a tree. When Ace knocks only one off (the very last mushroom, he hits it off the tree completely and you see) a metal spike that held all the mushroom props in place visible on the tree.
Continuity mistake: When Daniel is being chased by the Yakuzi in their black Mitsubishi Lancer Evo 6s, one of their Lancers crashes into the tanks. The car used for that crash is however a Lancer Evo 4, which is older than the Evo 6, and has a different front bumper, bonnet and rear spoiler. (01:17:25)
Continuity mistake: When the twins are singing about Brad for the talent show, and Michael was playing the piano (you have to listen and watch), his hands are suppose to go across the keys but he is still doing the fake up-and-down-hand-move.
Factual error: Near the end of the movie, Rob Schneider lets himself out of the police car. This would be impossible since the rear doors of police cars don't have handles on the inside.
Continuity mistake: When Joe is on the yacht talking to his father, Joe is mixing up martinis, pours them, and adds an onion to one, and then an olive to the other. The camera cuts away to his father and then cuts back and now the second martini has no olive, so Joe adds an olive again. (01:30:11)
Continuity mistake: When Babe is walking through the house, you will notice that several times his feet switch from muddy to clean as the camera angle changes.