She has been catapulted from 13 to 30, with magic dust involved, courtesy the 13-year-old Matt, but nothing is made of that except as an unexplained device. New York City, especially Central Park, but also every other slice of the place incorporated into the movie, seems hope-filled and easily livable, and save for Lucy there's no villain in Jenna's adult life, and even Lucy is not cast as monstrous, only as a nasty 13-year-old grown 17 years more devious. Chris, the one-time boy object of Jenna's yearning, is now a porky cab driver, and you have seen enough films to know that Matt will play a major role in Jenna's future. You don't know quite what might impede this before it is finally achieved, though I'm here to whisper in your ear, so to speak, that the device is not unique. In fact, not only is this a variation on the theme of Tom Hanks' "Big," though nowhere near as fine, it is also a strictly by-the-book version of this subset of the Cinderella story.