Character mistake: At the party, Fred is supposed to make a bbq, feeding about 50 people. But once he's got the fire going, he puts two lonely pieces of hamburger meat on top, to cook - only two.
Continuity mistake: Just after Miller, Casey, and Jeff Chang get away from the college's health center and steal the SUV, they plow through a row of street-side parking meters that snap off and hit the windshield, cracking it. Through subsequent shots, the windshield continually goes from being cracked to completely undamaged.
Continuity mistake: When Alan drops his driving gloves on the way out of the board meeting, the way they're arranged on the floor changes between shots.
Continuity mistake: Julia Louis-Dreyfus is getting her toe nails painted by her daughter's friend. The first shot is of her feet right next to each other. The very next shot, her legs are crossed.
Continuity mistake: In the gym before the lady says "why do we have to turn around" Roxanne is facing the front and then turns and then when the man says "if we please" Roxanne is turning around again.
Suggested correction: Roxanne was looking back at the janitor guy so therefore she didn't turn around twice.
Continuity mistake: Near the end of the movie Ryan Phillippe is in a hospital bed with oxygen connected to his nose. When Anna Paquin reaches over to touch his cheek it is gone.
Continuity mistake: Just after Nick and Billy find professor Xavier and get back with the others, the sun changes between shots.
Continuity mistake: Near the end of the film when Hannah goes to Elliot's house to make up with him, she parks her Volvo SUV directly in front of the door. In fact, the car is visible behind her when she enters the home. Then when she leaves after they argue, she has to walk pretty far up the street to her car, giving him time to catch her.
Revealing mistake: Montana gets a call from Sam who is informing her about Damon Diesel. The camera shows Montana rushing up to the phone which is on the table. When the phone rings it is not on the call screen, it is on the contact page. Shortly after Montana's mother comes and leaves Montana glances at the clock and hurries to call Sam. She raises her phone to her cheek and ask "Sam what's the flight number?" If you look closely, the call is not actually being made as her cheek is pressing different icons on her phone. (00:23:55 - 00:25:40)
Other mistake: Keira Knightley looks down at her phone, there is a beautiful female hand holding the phone with long slightly curved nail beds. This is not Keira's hand which is seen many other times times throughout the film. She has shorter nailbed and flat nails. (00:22:37 - 01:13:56)
Other mistake: Throughout the film, you can frequently see many people's faces blurred, phone numbers blurred, store-fronts blurred, etc. This is because the production could not afford the rights to show these people, places and things, and simply blurred them out.
Continuity mistake: Bera and Bea have multiple sequences where he complains about his roomie Ugo who lashed back at him after all the abuse he had to take from him. There's a plastic cup on the flush tank; in one of the scenes, in between others, the cup is suddenly in a different spot on the tank (more to the right) and the straw is tilted the opposite way than before. (01:11:00)
Continuity mistake: Our group of jewelry thieves are on their way to "Zugarramurdi" in a stolen taxicab. The "green soldier" Antonio began to wash the color from his face. Nevertheless you can see, depending on the camera angle, that the green color is sometimes seen on his nasal bone and sometimes not. (00:20:55 - 00:21:30)
Character mistake: When Sheriff Flemings arrives at the gas station murder scene, Deputy Baldridge is already there taking photographs. The pair exchange a few words and Baldridge says he can't find the victims body. The pair then look up to see three of the flying monkeys noisily eating Mr Sites corpse on the roof of the gas station. Apparently Baldridge didn't notice this the whole time he was there. (01:03:19)
Other mistake: The last half of the movie is based in France. Mr. and Mrs. Jones are being rescued by a French man that she has been texting. He comes to them on the cliffs in his boat. The flag waving behind them is the flag from the Netherlands not the French flag. They have the same colors but the stripes on the French flag are vertical while the ones on the Dutch flag are horizontal.
Factual error: Don Jon is set in a New Jersey town. A commercial for Hardee's/Carl Jr's restaurants comes on the TV during a family dinner. These restaurants are not in the New Jersey/New York area at all.
Continuity mistake: The English teacher enters the classroom for her first lesson. She writes her name on the blackboard. Her name is written in at least 2 different styles that randomly switch during the scene (easy to tell from the double underline; the two strokes connect with the circle of the capital initial of her name, or stop at the tail). (00:07:00)
Continuity mistake: The protagonist is told about the budget cuts that will lead to the library shutting down. During the scene, the strap of his hat keeps going back and forth in front / behind his ear. (00:02:05)
Deliberate mistake: The whole premise of the movie is 'artistic license' so to speak; the protagonist signs himself up to the bone marrow donors register, called ADMO in his country (Italy). But he is still a minor, and that is strictly not allowed. Not even with a written consent of the parents as shown in the movie.
Continuity mistake: The layout of the two slices of pizza on the tray and the position of Tyler's fork on his plate differ after Matt reaches the table. The slices of pizza are touching, then spread apart like a "V." Tyler's fork moves from being diagonally across his plate with tines facing him to being situated near the edge of the plate with tines facing Jessica. (00:13:19)