Revealing mistake: When Harkin Banks almost loses control and skis through the lodge, the jump ramp is visible as the woman opens the door. (01:29:45)
Revealing mistake: Rocky says "cut my eye" during the fight scene, if you watch closly you can see the man actually squeeze a tube full of red stuff inches away from his eye. It's really quite funny... (01:49:20)
Revealing mistake: When Leslie is fighting the soldiers, one soldier hits a second soldier with his rifle. The rifle can be seen to bend around the soldier's body and then straighten again. (02:12:10)
Revealing mistake: In the celebration scene at the end, there are multiple times when you see huge sections of the stadium with no people in them. The most obvious is when WMH jumps into Jake's arms. (01:39:05)
Revealing mistake: During the fight scene, when Jake gets out of the car to fight the three guys in the yellow Hummer, Max lifts up his video camera after Jake throws his first punch. But after the fight, when all of the students are watching the fight on the net at school, it shows that Max is recording before the fight even begins.
Revealing mistake: Before Josh tells his mom about Buddy, Buddy starts to push the basketball with nose down the stairs. While he is doing this, you can see the treat put there just before the ball moves.
Revealing mistake: Throughout the extended scene where Ralph was training with Father Hibbert in pouring-down rain, both characters' faces were completely dry when they should have been completely wet.
Revealing mistake: In the scene where Stripes is looking in the water at his reflection, his body and the reflection don't quite match up. You can tell by his movements that his reflection is computer generated. (This is verified by the audio commentary.)
Revealing mistake: As Machine Gun Joe runs slowly runs over a fisherman in a small brook, he stops and "peels out" on his head. You can see a film crewman in the driver's seat doing the actual carnage.
Revealing mistake: If you watch Herb's wife Patty drink her hot chocolate, it is very easy to see that the cup is empty.
Revealing mistake: When Thornton and Lou are making the Bruce Springsteen sign, the student at the table is supposed to be writing on a poster but you can see that the marker is not touching the paper.
Revealing mistake: When Herbie is being pulled from the truck at Crazy Dave's, Herbie goes into reverse and the camera does a closeup shot of one of the rear wheels reversing. If you look carefully, you can see an extra set of small wheels behind the tyre which are obviously propping the car up enough so that the cars proper wheels will only skid and not get any traction.
Revealing mistake: The ball Lou Gehrig hits that smashes a window doesn't come off his bat. It comes from behind him.
Revealing mistake: In the game against Liverpool, there is a reversed shot after Harris scores the first goal. It is fairly obvious since all of the players' numbers are backwards, in addition to the advertisements in the background. (01:45:25)
Revealing mistake: During the night surfing scene notice that the sun is evident in the background (look closely it does not appear long). There are also shots where you can see clouds and faint blue sky. Moments later you see Keanu and Lori sitting in the water with completely different lighting which was actually taken at night and further distinguishes that the surfing shots were not actually done at night time. I heard the scene was shot during the day with a filter so it looked like it was shot at night.
Revealing mistake: When Calvin falls out of the tree, he lands on the ground on his back. This would at least knock the breath out of him, but he is not hurt at all.
Revealing mistake: After William Macy interviews Jeff Bridges and when the narrator is describing Seabiscuit's fans (the scenes are about an hour apart), you see shots of people in trees. They are the same shot.
Revealing mistake: During the film, the Nike tick on the Arsenal shirt is a reversed tick, revealing a flipped shot.
Revealing mistake: In this film, you can see where the present-day lines on the basketball court have been sanded off and "50's" style lines added.
Revealing mistake: When Walther Matthau is making sandwiches for his poker pals (during the movie's first poker game), Matthau drops a slice of bread on the kitchen floor. If you look at his hand, you'll see that he flicks his thumb to make the slice of bread fall.