Continuity mistake: In the scene where Edward goes back to the highway from rescuing Bella. We see he stops the car when he turns, when the camera changes we see the area around them moving but we never heard or see the car accelerate.
Continuity mistake: On Bella's first day of school, when Eric comes up and introduces himself, Tyler passes them, going the opposite way, and looks at Bella. But in the last scene he was sitting at his car, making no move to leave, let alone go back to the parking lot. (00:06:25)