SCHOOLS frequently dismiss sexual assault between students as part of the "rough and tumble" of high school life, a report by the Australian Institute of Family Studies shows.

And while one in seven teenage girls has been the victim of a sexual offence, most are reluctant to report them because they know the perpetrator or they fear they will not be believed.

The report urges schools to take tougher measures to ensure disclosure of sexual abuse.

It finds that cases of sexual assault between peers often go unacknowledged. According to the report, about 14 per cent of people aged between 12 and 20 have been sexually assaulted, along with 3 per cent of boys - mostly by people they know.

"The abuse of young people by people in authority has been the focus of public concern," the institute's general manager of research, Daryl Higgins, said.

"However, sexual assault between young people at parties and in dating relationships is often still not acknowledged.

"Within schools, peer-to-peer sexual assault has been unacknowledged because the assault has taken place outside school grounds or is interpreted as being part of the rough and tumble of high school life."

The report recommends that schools create safe areas for students to seek support, teachers receive training to enable them to deal with victims, and victims and perpetrators are immediately separated.