The New York Times reports:

In 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.

Further:

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.”

Recently, a Mississippi 17-year-old wasn’t allowed to wear a tux for her yearbook photo:

At Wesson Attendance Center, a Mississippi public school, just that sort of fight erupted over senior portraits. Last summer, during her photo session, Ceara Sturgis, 17, dutifully tried on the traditional black drape, the open-necked robe that reveals the collarbone, a hint of bare shoulder.

“It was terrible!” said Ms. Sturgis, an honors student, band president and soccer goalie, who has been openly gay since 10th grade. “If you put a boy in a drape, that’s me! I have big shoulders and ooh, it didn’t look like me! I said, ‘I can’t do this!’ So my mom said, ‘Try on the tux.’ And that looked normal.”

Shortly thereafter, students were informed that girls had to wear drapes for yearbook portraits; boys, tuxedos.

The Mississippi chapter of the American Civil Liberties Union wrote to the school. Rickey Clopton, superintendent of Copiah County schools, did not return phone calls. Last month he released a statement affirming that the school’s decision was “based upon sound educational policy and legal precedent.”

Last month, Veronica Rodriguez, Ms. Sturgis’s mother, paid for a full-page ad in the yearbook that is to include a photograph of her daughter in a tuxedo.

Schools have some freedom in how they will respond:

But generally, courts give local administrators great latitude. In Marion County, Fla., students must dress “in keeping with their gender.” Last spring, when a boy came to school wearing high-heeled boots, a stuffed bra, and a V-neck T-shirt, he was sent home to change.

“He was cross-dressing, and it caused a disruption in the normal instructional day,” said Kevin Christian, a district spokesman. “That’s the whole point behind the dress code.”

Sociologists weigh in on how non-conformity can lead to harassment:

“There are other places where there are real safety issues,” said Barbara Risman, a sociologist at the University of Illinois who studies adolescent gender identity. “Most boys still very much feel the need to repress whole parts of themselves to avoid peer harassment.”

Last fall, Stephen Russell, a professor at the University of Arizona who studies gay, lesbian and transgender youths, conducted a survey of about 1,200 California high school students. When asked why those perceived as not as “masculine” or “feminine” as others were harassed, a leading reason students gave was “manner of dress.”

So…

When a principal asks a boy to leave his handbag at home, is the request an attempt to protect a student from harassment or harassment itself?