An overstuffed composite of two popular young-adult novels by Sarah Dessen, How To Deal may first appear to be as frivolous as its slangy title; it looks like another airy vehicle through which pop star Mandy Moore can ingratiate herself to pre-teen girly-girls. Yet there's a surprising intelligence and gravity working beneath its bubbly surface, informed by an unusual degree of empathy for its adolescent audience and a rare willingness to confront the darker regions of youth experience. The two books provide far too much story for one movie, resulting in a choppy rhythm and several subplots that come to abrupt resolutions. But the busyness also yields an ambitious and remarkably full-bodied take on the cycle of life, with birth, death, romance, marriage, and divorce all squeezed into the space of one transitional year. A brighter and more naturalistic performer than many of her billboard forebears, Moore breaks free from the calculated wholesomeness of last year's A Walk To Remember and conveys the thorny anxieties that dog the children of broken homes. Allison Janney and Peter Gallagher lead a skilled supporting cast as Moore's parents, who split after Gallagher–great as a long-in-the-tooth hipster DJ who bills himself "The Big Dog Of Soft Rock"–leaves his wife for a young, ditzy blonde mistress. Janney's frothing bitterness isn't lost on Moore, who enters a tentative courtship with dark-horse romantic Trent Ford, warning him that "the best way to ruin a relationship is by starting one." Meanwhile, she receives mixed signals from the melodramas around her, including older sister Mary Catherine Garrison's impending marriage to an uptight prig (Mackenzie Astin) and a close friend (Alexandra Holden) who learns she's pregnant after her boyfriend dies suddenly from a heart defect. While far better than it has any right to be, How To Deal isn't above the synergistic music-video montages and bits of low comedy that riddle other teen fare, though even an unfortunate old nugget like a grass-toking granny is handled with more dignity and nuance than might be expected. At its heart, the film touches on the premonitory fear of divorced children that love always ends badly, a worry that tempts them to withdraw from romance the moment they start to care about somebody. It's rare for screen teenagers to have their affairs complicated by more than missed phone calls and misunderstandings, let alone the heavy distractions of a messy divorce, a premature death, and single motherhood. (The use of The Flaming Lips' soaring "Do You Realize??," a bittersweet song about the fragility of life and its transcendent possibilities, seems particularly apropos.) On every front, How To Deal wraps up as predictably as anyone would expect, but at least it sweats for every feel-good moment it gets.