For her schoolmates, the Lebanese-American teen is a "towelhead" like the Iraqis America is off fighting in the 1991 Gulf War. Jasira? She's just confused - about men, about menstruation, and yes, about that humid feeling she gets when looking at billboards of scantily clad lap dancers in provocative poses.

If Juno, the tough-talking, soft-hearted high-schooler in her first trimester, made teenage pregnancy family-friendly, then can Jasira, the middle-schooler simultaneously dealing with budding body, blossoming erotic feelings, racist schoolmates, and parent's divorce, do same for teen sexuality?

Smartly adapted from the 2005 novel by Alicia Erian, Towelhead, Alan Ball's brutally honest and edgily funny story centers on Jasira (sensational Summer Bishil, 20), whose personal calculus is harder to solve even than multi-variable algebra.

Ball, the creator of Six Feet Under and screenwriter of American Beauty, dares us to look at this unconscious beauty, whose inky tendrils frame her almond eyes and ripe-plum lips, without projecting our own fantasies and fears. The result is a movie about the many forms of social and sexual abuse that does not make the abusee a victim but victor.

Then, he reverses angle and shows us how the world looks through her confused eyes, a rapidly shifting universe where every given is peremptorily taken away. One night, she's the subject of parental love, next morning an object of inappropriate lust. Seeking the adult tenderness withheld by her nervous parents, Jasira confuses sex for emotional intimacy.

Not since Splendor in the Grass has there been such a candid and sympathetic account of the mixed messages, double-standards, giddy highs and hormonal free falls experienced by teenage girls. For Jasira, every day is her own personal Tower of Terror ride, an elevator trip to the penthouse of possible pleasure, one that abruptly plunges to the sub-basement of shame.

When Mom's live-in beau volunteers to give Jasira a bikini wax, Mother (Maria Bello) immediately dispatches Jasira to Houston to the care of her courtly father.

A gentleman of Old World values, Rifat (Peter Macdissi) nonetheless enjoys New World prerogatives. Still, he is so scandalized when his budding daughter comes to the breakfast table in short-shorts that he belts her.

Is it any wonder that this human shuttlecock in her parent's divorce badminton and ongoing target of middle-school intolerance responds to the appreciative attentions of Mr. Vuoso (Aaron Eckhart), the lecher next door? Vuoso, an army reservist about to be deployed to Kuwait, is intrigued not only by his son's new babysitter, but also by her interest in Vuoso's stash of Playboy magazines.

Unlike the thematically related American Beauty - surreal, and sometimes shrill, about the domino effect of sexual inappropriateness in suburbia - Towelhead has a realistic style and deadpan tone. Here Ball frames every situation for its potential horror and humor.

Speaking in a twang that wavers between animated girl and anesthetized teen, Bishil delivers a perfectly pitched performance as the girl both frightened and delighted by her biology. With his turn as the super-proper parent blind to his own hypocrisy, Macdissi mines the depths of the situation's tragicomedy.

Also on hand is Toni Collette, who is to indie movies as the heart is to the human body, playing Melina, a neighbor who thinks that Jasira might learn more from Changing Bodies, Changing Lives than from Playboy.

Towelhead never asks the easy question, how do we protect our innocent girls? It poses harder ones: How do we get beyond sentimentalizing innocence and instead teach our girls - and boys - how to navigate the responsibilities of experience in order to enjoy its pleasures? Ball has made that rare thing, a movie about the many forms of social and sexual abuse that does not reduce the abusee to a victim, but celebrates her resilience and capability of growth.

Towelhead ***1/2 (out of four stars)

Written and directed by Alan Ball. With Summer Bishil, Peter Macdissi, Maria Bello, Aaron Eckhardt and Toni Collette. Distributed by Warner Independent Productions.

Running time: 1 hour, 56 mins.

Parent's guide: R (for strong disturbing sexual content and abuse involving a young teen, profanity).

Playing at: Ritz Five, Showcase at the Ritz/NJ