Continuity mistake: When Jay and Terri are dancing on the rooftop, the position of Terri's hand on Jay's chest keeps changing with each shot.
Continuity mistake: When Terri's brother is filming Terri and her friend leaving the school, the view from within his video camera says he has been recording for one minute and seventeen seconds, which turns into eighteen. But when we come back to the view from his video camera a few shots later, he is at one minute and sixteen seconds. (00:03:05)
Continuity mistake: When Robin has her mental breakdown about not getting the solo she goes out side and begins banging her head against a vending machine. Then Jay comes to talk to her they walk to the edge of the balcony and her shirt goes from collar bone height to almost showing her breast.
Continuity mistake: At the end of Terri and Jay's song, Terri changes her position (which hand is holding the mic, etc) in between each song. It might be deliberate, but it's a mistake none the less, since this was supposed to be filmed in real time. It looks like a music video, which it is indeed not.
Continuity mistake: Terri changes sides of the stage during the last song. It shows her walk to one end, then does close up then wide shot, and she is on the opposite side of Jay. Happens a couple of times.
Answer: All of the singing that Hilary Duff did in the film is her own. This is stated in the credits of the songs she did.
moviemogul