Looking into state education records and federal crime data, a yearlong investigation by the Associated Press uncovered roughly 17,000 official reports of sex assaults by students from fall 2011 to spring 2015.

AP reported that sexual assaults among the nation's 50 million kindergarten to Grade 12 students is greatly under-reported because some states don't track them and others vary widely in how they classify and catalog sexual violence.

A number of academic estimates range sharply higher.

"Schools are required to keep students safe," said Charol Shakeshaft, a Virginia Commonwealth University professor who specializes in school sexual misconduct. "It is part of their mission. It is part of their legal responsibility. It isn't happening. Why don't we know more about it, and why isn't it being stopped?"

Elementary and secondary schools have no national requirement to track or disclose sexual violence, and they feel tremendous pressure to hide it, AP reported. Even under varying state laws, acknowledging an incident can trigger liabilities and requirements to act.

And when schools don't act — or when their efforts to root out abuse are ineffectual — justice is not served.

AP focused on a former student at Brunswick (Maine) Junior High School who said he was taunted, beat up, harassed, chased and raped. AP found that school administrators allowed the bullying of Chaz Wing to escalate, and then failed to adequately investigate his allegations of sexual abuse.

Wing told police, child-abuse investigators and lawyers under oath that he kept quiet about the assaults for nearly a year because of threats against him and his family if he talked.

Sexual abuse allegations can be difficult to investigate. Because many accusers initially keep quiet, physical evidence can be long gone once investigators step in. Often, there are no eyewitnesses, leaving only the conflicting accounts of the accuser and the accused.

What Wing told authorities and investigators — multiple times over four years — remained consistent, an AP review of government and court records shows. And a child-abuse examiner wrote of "strong evidence" that Wing was sexually assaulted.

The school district staunchly defends how it handled its investigation. The junior high principal said his inquiry determined that the sexual assaults were "very unlikely." One of the accused boys, he noted, had never even heard of anal rape.

"There is — as there should be — always an inclination to believe allegations of sexual assault at the outset," district lawyer Melissa Hewey said in an email to AP. "But sometimes, the evidence compels the conclusion that those allegations are false."

"The little boys who were accused," she said, "are the real victims in this case and they deserve to be protected."

A HIDDEN PROBLEM

Children remain most vulnerable to sexual assaults by other children in the privacy of a home, according to AP's review of the federal crime data, which allowed for a more detailed analysis than state education records. But schools — where many more adults are keeping watch, and where parents trust their kids will be kept safe — are the No. 2 site where juveniles are sexually violated by their peers.

The sexual violence that AP tracked often was mischaracterized as bullying, hazing or consensual behavior while it should have been classified as rape, sodomy and forced oral sex and fondling. It occurred anywhere students were left unsupervised: buses and bathrooms, hallways and locker rooms. No type of school was immune, whether it be in an upper-class suburb, an inner-city neighborhood or a blue-collar farm town.

And all types of children were vulnerable, not just kids like Wing who have trouble fitting in.

About 5 percent of the sexual violence involved 5- and 6-year-olds. But the numbers increased significantly between ages 10 and 11 — about the time many students start their middle-school years — and continued rising up until age 14. They then dropped as students progressed through their high school years.

The AP counted only the most severe forms of sexual assault, not behavior like kissing on the playground.

Associated Press journalists Robin McDowell reported from Brunswick; Reese Dunklin and Emily Schmall from Dallas; and Justin Pritchard from Los Angeles. Part 2 of this series will be published tomorrow.

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