A movie about--but possibly not for--teenagers, Thirteen paints a grim picture of American youth and their daily temptations. Director Catherine Hardwicke's film follows smart and self-assured Tracy (Evan Rachel Wood) as she spirals uncontrollably from Little Miss Perfect to Every Parent's Nightmare in one school year. With her new partner in crime, popular girl Evie (Nikki Reed), Tracy begins to experiment with sex, drugs, alcohol, shoplifting, and self-mutilation--partly in reaction to the problems her mother (Holly Hunter) has had with her absentee husband and her recovering addict boyfriend (Jeremy Sisto). Repeatedly and reasonably, Thirteen links the teens' increasingly bratty behavior with their growing materialism, nurtured at the toxic teats of television, brand names, and corporate chains. There's also a wealth of precocious talent on display here: Both lead teen actresses are convincing, and Reed is credited with co-writing the screenplay. But for all its insight and extremity--checking in much rougher than Girl, Interrupted, if slightly softer than Bully--Thirteen careens a little too cartoonishly over-the-top. Particularly in its failure to differentiate between genuinely unhealthy behavior and, say, belly-button piercing, it teeters dangerously on the precipice of preachy after-school special material.