Continuity mistake: When the boys are on the Nemesis Inferno, Will sits at the front while the rest sit behind him, and this leaves the right outside seat free. However, when the roller coaster is moving, the mounted camera shows that Simon, Jay and Neil have all moved one seat to the right, meaning that Simon is now on the right outside seat instead of it being free.
Factual error: About halfway through the scene of the boys riding the Nemesis Inferno, the coaster train speeds through an inverted 360 degree loop. In actual fact, this loop occurs right at the beginning of the ride, whereas this scene makes it appear to occur near the end.
Deliberate mistake: In the scene where Jay spots the "car full o' muff" and they follow the car until it turns left (just after Jay says he'd "give a left bollock for em"), when it pulls away, the shot is flipped. The number plate is reversed, all of the logos on the back of the car are backwards, and the car is actually turning right, as it heads to the right hand side of the road. The shot is just flipped to make it look like they're turning left.
Continuity mistake: After Will's taken his shoes off, they are taken by the group of younger boys behind him who start throwing the shoes between them as Will tries to get them back. The boy in blue with the number 23 on his jumper and the dark blue strip down the arms changes position between shots, from left of shot to back of shot, to left of shot.