The last time classroom attire was this contentious was the late 1960s and early 1970s, when the most high-profile cases centered on boys. According to Jo Paoletti, author of the forthcoming book “Sex and Unisex: Fashion, Feminism and the Sexual Revolution,” young men with long hair were sometimes attacked by their peers. In an all-too-familiar scenario, it was the victims who were blamed for such assaults, accused of provoking classmates with their “distracting” appearance. While girls who violated dress codes were sent home to change, boys were suspended or expelled. Their parents also disproportionately lawyered up: By 1974, there were 150 court cases involving young men’s hairdos.

Boys run afoul of dress codes when they flout authority: “hippies” defying the establishment, “thugs” in saggy pants. For girls, the issue is seductiveness, and that, too, has become politicized, exposing a new generation gap.

Today’s canny girls, emboldened by #YesAllWomen Twitter culture, scold their elders, “Don’t tell us what to wear; teach the boys not to stare.” They are correct: Addressing leering or harassment will challenge young men’s assumptions. Imposing purdah on middle school girls does the opposite.

Even so, while women are not responsible for male misbehavior, and while no amount of dress (or undress) will avert catcalls, cultural change can be glacial, and I have a child trying to wend her way safely through our city streets right now. I don’t want to her to feel shame in her soon-to-be-emerging woman’s body, but I also don’t want her to be a target. Has maternal concern made me prudent or simply a prude?

More than that, taking on the right to bare arms (and legs, and cleavage and midriffs) as a feminist rallying cry seems suspiciously Orwellian. Fashions catering to girls emphasize body consciousness at the youngest ages — Gap offers “skinny jeans” for toddlers, Target hawks bikinis for infants. Good luck finding anything but those itty-bitty shorts for your 12-year-old. So even as I object to the policing of girls’ sexuality, I’m concerned about the incessant drumbeat of self-objectification: the pressure young women face to view their bodies as the objects of others’ desires.