I did a double take at the end of this kids comedy when the PG rating advised me that "some material may be unsuitable for children." In fact it's eminently suitable for children, fully inhabiting their world and finding real laughs there without resorting to sentiment, condescension, or snarky in-jokes for the adults. The heroes (Zachary Gordon and Robert Capron) are a couple of junior-high losers whose friendship is tested by the shark-filled waters of their school; the movie is remarkably attuned to that awful period when you're not just known but sometimes doomed by the company you keep. The script was adapted from a novel by Jeff Kinney, but director Thor Freudenthal (Hotel for Dogs) probably deserves the credit for the movie's unforced comic rhythm.