Continuity mistake: When Sarah is in the library, Kate comes and leans on the table next to her. When we first see her close up, her ponytail is dangling by her head, it zooms out and the ponytail is on her back, again it zooms in and is in front of her face, zooms back out and it's on her back again.
Continuity mistake: When Caleb is taking Sarah to his dad's house it's raining and they are in a convertible with the top down so they would get wet. But then when the shot changes to the inside the car, it's not raining anymore.