WASHINGTON — Federal, state and local agencies aren’t doing enough to monitor and prevent sexual abuse of children by school employees, resulting in a spotty reporting system that might underestimate the number of children who are sexually abused in schools, according to a new congressional report.

Although 46 states require officials to report child sexual abuse and 43 have penalties for failing to do so, many schools settle reports of allegations or suspicions of abuse within school districts because they don’t fully understand or comply with existing requirements, according to the Government Accountability Office, the investigative arm of Congress.

“States have to understand reporting and monitoring is not an option,” said Rep. George Miller, D-Calif., who requested the study. “It is the law and it is our obligation to keep our children safe. Such confusion is unacceptable.”

Though the extent isn’t clear, state and school districts also differ significantly on how they handle background checks for potential public school employees, awareness and prevention of child sexual abuse, and employee codes of conduct. Some schools interpreted Title IX – a federal education law against sex discrimination – to exclude incidents between children and teachers, the report said.

“We may not know about many cases of child sexual abuse simply because the right channels aren’t being used,” said Shannon Waters Russell, a therapist at Prevent Child Abuse America, an advocacy group. “That means sexual misconduct is essentially covered up.”

Also, federal agencies don’t systematically identify the extent of sexual abuse by school employees, according to the GAO.

Schools need to use more resources to prevent such abuse by providing more staff training, said Jim Hmurovich, the president and CEO of Prevent Child Abuse America. Only 18 states require school districts to provide training on sexual abuse and misconduct, the report says.

Perpetrators often groom victims by offering gifts and kind words, emphasizing how employees can exploit the trusting atmosphere in schools, Hmurovich said.

“Teachers sometimes spend more time with their students than parents,” said Daphne Young, a former teacher who handled cases of child sexual abuse at Presidio High School in Tucson, Ariz. “They have every opportunity to groom and influence a child’s mind. We should be very concerned.”

The report follows up on a 2010 GAO report that highlighted 15 cases of sexual abuse in schools and a 2004 U.S. Department of Education report that said nearly 10 percent of students have sexual contact with school employees before they graduate.

The U.S. Department of Education will clarify schools’ Title IX obligation to prevent and report sexual violence in the coming months, department spokeswoman Dorie Nolt said.

“In the department’s enforcement efforts, we find that some of the most egregious violations happen when no one is paying attention to these issues,” she said.

In a separate statement, the Education Department said it would expand sexual misconduct training to “a wider audience, including school volunteers” and find more effective ways to analyze the prevalence of child sexual abuse.

“Abusers are known to exploit relationships of trust,” said Young, the president of communications and prevention education at Childhelp, an advocacy group that helps victims of child abuse and at-risk children.

“If you haven’t taken care of officially reporting a case, you’ve just allowed a known offender to go into another locker room or another science lab. We can’t let that happen to our children,” Young said.