Other mistake: Every time somebody climbs to the attic in the "lake house", you see a small, dark, enclosed chamber with some abandoned stuff. However, as soon as you see the "lake house" from the outside, it is a single-level construction entirely made of glass, with no inside staircase or ladder, and three smaller glasshouses on the roof. There is not a single wooden panel to enclose the attic, nor any construction in the house that looks like it could be that attic.
Suggested correction: It's not a "dark, enclosed chamber"; it's a glass surround with part of the windows darkened, but others letting light in. The ladder is shown near the end of the movie (when he's putting the box of letters away) to fold up into a small space, and the "attic" is merely a small space, easily the height of the roof plus one of the glass bits you can see from outside the house.
After looking at many photos of the house, there is no space for the attic.
Other mistake: When Amanda's driver brings her to the cottage for the first time, he tells her he can't drive her up there because he would not be able to turn around, but the same driver picks her up at the cottage when she is leaving and presumably has no issue turning around at all, and you can see it's a flat field in front of the cottage.
Other mistake: Gray is at the office and wants to call Dunn Hamilton Investments Customer Relations on the note pad but the 1-800-INVEST isn't enough digits for a complete phone number.
Other mistake: During the musical auditions, the pairs audition doesn't start until halfway through the auditions. But the disturbing dancers were a pair audition and Ryan and Sharpay were the only pairs.
Other mistake: Just after the valley floods, Manny is seen pushing a log to pry the rock out blocking Ellie's way out. You can notice that Manny is pushing it the wrong way. (01:08:40)
Other mistake: Frankie tells Vanessa that he brings his son to the park on Saturdays and would like to meet her there. It shows in another scene from that day that Nikki, the foster child, had been in school that day so it couldn't have been a weekend day.
Other mistake: When Julia is trying to pop her zit with a plier, it's obvious she isn't applying any pressure.
Other mistake: Watch the Crown Princes body after he's shot himself in the head at the end of the film. As Inspector Uhl tells the men who broke in what happened, the Crown Prince is still breathing very heavily and noticeably.
Other mistake: When Helen kills the zombie bully she fires 9 shots from a 6 shot revolver.
Other mistake: When Mutini first gets shot, the gunfire supposedly comes from inside the vehicle, but the windows and doors are closed, the glass doesn't shatter when the shots are fired. There are no visible bullet holes when the door is opened.
Suggested correction: He was shot through the door. There are two visible bullet holes in the door when the shots ring out and when the door opens. Just below the window.
Other mistake: In the very beginning of the movie, we first meet John Tucker as he makes a slam dunk. Obviously, this would be worth 2 points. However, if you watch the referee behind John, he signals a 3 point shot. (00:03:00)
Other mistake: In the beginning, Aquamarine exclaims "My fingernails! They've never been this color before!" But her nails don't actually change colour until a few shots later.
Other mistake: In one of the air battles, the one where our heroes come to aid to a platoon of infantry harassed by German Fokker D.I's, the plane of Lowry is under fire after he downed an enemy airplane. In one shot, you can see he gets multiple hits just behind the pilot seat. Since these planes are barely armoured, say not at all, Lowry should have been punctured by the bullets at his back as well, instead of being completely fine. (01:16:00)
Other mistake: Just after Paula shoots the last of the Devil Babies, as he turns and says "Aw man", his back is devoid of paint from the fatal volley.
Other mistake: After the piano is delivered to the Girl's house, we see her mom cooking. There's obviously nothing in the pan despite her vigorous stirring. (01:19:35)
Other mistake: When Jenny and Matt first enter his apartment, the deadbolt on the door is intact. Later, when Professor Bedlam's minion kicks the door open the plate and deadlatch are missing. The act of kicking the door open might destroy the striker plate in the door jamb, or it might blow the entire lock body through the door, but it couldn't neatly remove the plate and bolt alone.
Other mistake: Why is it that, at the wild party, the guys at the barn are shocked to find out how long Simon's "unit" is? Didn't they see it when he showed up to the fancy ball with only a black tie on?