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In May, the Department of Education named 55 colleges and universities facing sexual violence investigations. The unprecedented list – which includes some of America's most prestigious colleges and has since climbed to 86 institutions – circulated widely and proved to be a powerful tool for raising awareness about college sexual assault.

But the list was missing something: the K-12 school districts that also face federal inquiry for how they handle sexual violence.

All schools that receive federal funding, including every public school district, are beholden to Title IX, which requires them to respond to sexual assault reports in specific ways. And it isn't as if sexual violence is confined to college. A 2008 survey of more than 1,000 students found that 53 percent of high school girls suffer some degree of sexual assault – anything from unwanted touching to rape – by a peer, and that 39 percent of peer-on-peer sexual assaults occur at school.

Unwanted peer touching was reported by 51 percent of high school girls, while 12 percent said they were raped.

But despite the prevalence of the problem, high schools have largely avoided the blistering scrutiny that colleges have faced over the issue of sexual violence. That isn't because high schools are better at handling the issue, according to Colby Bruno, senior legal counsel at the Victim Right's Law Center. It's quite the opposite.

“High schools are basically where colleges were like 15 years ago — in the Dark Ages,” she told America Tonight in July.

Bruno, who represents sexual assault victims, said 9 out of 10 high schools that she has contacted about sexual violence cases don’t realize that Title IX even applies to them.

But it does. And when the federal government believes a school district may have failed to uphold the civil rights law – in response to a complaint from a student, parent or faculty member – it investigates. That's what's currently happening at nearly two dozen K-12 districts across the country, according to a list obtained by America Tonight from the Department of Education's Office of Civil Rights.

Below, you'll find a map and full list of the 23 districts.