n recent years, a growing number of teenagers have been dressing to articulate -- or confound -- gender identity and sexual orientation. Certainly they have been confounding school officials, whose responses have ranged from indifference to applause to bans.

Last week, a cross-dressing Houston senior was sent home because his wig violated the school's dress code rule that a boy's hair may not be "longer than the bottom of a regular shirt collar." In October, officials at a high school in Cobb County, Ga., sent home a boy who favored wigs, makeup and skinny jeans. In August, a Mississippi student's senior portrait was barred from her yearbook because she had posed in a tuxedo.

Other schools are more accepting of unconventional gender expression. In September, a freshman girl at Rincon High School in Tucson who identifies as male was nominated for homecoming prince. Last May, a gay male student at a Los Angeles high school was crowned prom queen.

Dress code conflicts often reflect a generational divide, with students coming of age in a culture that is more accepting of ambiguity and difference than that of the adults who make the rules.

"This generation is really challenging the gender norms we grew up with," said Diane Ehrensaft, an Oakland psychologist who writes about gender. "A lot of youths say they won't be bound by boys having to wear this or girls wearing that. For them, gender is a creative playing field." Adults, she added, "become the gender police through dress codes."