Thou shalt not wear skinny jeans.

So saith a new dress code at Kenilworth Junior High in Petaluma, Calif., KTVU reports.

On April 4, the school held an assembly for its female students telling them they were no longer allowed to wear yoga pants, leggings or tight jeans because it was distracting the boys.

After outrage erupted among parents and students alike, Kenilworth Principal Emily Dunnagan modified the policy, saying tight jeans are permissible but leggings aren’t, Petaluma Patch reports.

“The concern is we don’t want undergarments showing,” Dunnagan said. “The goal is to teach kids to respect themselves and dress appropriately.”

Dunnagan added that boys must follow a similar dress code that forbids them from wearing baggy pants. If caught wearing the underwear-exposing garments, boys will be given a rope to belt their pants and girls will have to change into sports pants.

Despite the school’s effort to explain its changes to the dress code, some still see it as sending a dangerous message to teenage boys.

“It teaches boys that there are certain circumstances under which they don’t have to respect their classmates’ bodies and boundaries,” wrote Chloe, a Feministing blogger. “This is how you teach rape culture to 12-year-olds.”

“Girls can't wear tight pants not because they've done anything wrong, but because their male classmates are acting like immature little jerks,” Jeanne Sager at theStir blogged.

Jerelyn Kruljac, mother of a Kenilworth student, agrees. She wore skinny jeans in solidarity with her daughter the day after the dress code was announced, KTVU reports.

"Boys need to be taught to respect women no matter what they're wearing, and that's a big deal," Kruljac told the news outlet.

Kenilworth Junior High is not alone. It’s one of many schools waging a “War on Leggings.”

Schools in Vermont, Washington, D.C., and Minnesota have enacted similar dress code changes.

"This new trend doesn't seem right; it's troubling," Minnetonka, Minn., High School Principal Dave Adney told the Minneapolis Star-Tribune. He sent an email to parents asking them to speak with their daughters about dressing more modestly – but didn’t ban students from wearing the spandex pants.

But his candor says it best.

"Cover your butts up -- I'm just going to say it straight up. We're seeing too much," he said.