Police are being called to Victorian schools three times a week to investigate sex offences that are often perpetrated by children.
The revelation comes amid reports of a surge in the number children sexually abusing other children in the wider community that has been linked by treatment services to family violence and pornography.
New data from the Crime Statistics Agency data shows 170 sexual offences were committed in Victorian state, independent and Catholic school grounds last year, including 41 during school hours.
With around 80 per cent of offenders 18-years-old or under, experts say schools are struggling with the controversial issue.
Angela Sdrinis, who runs a law firm that specialises in institutional abuse, said she was receiving more reports of child-on-child sexual abuse in schools.
"Schools are a lot more informed about adult-on-child and historical abuse but I think the child-on-child abuse is very hard to come to grips with," she said.
"It's a bit like in the old days when a priest was accused of sexual abuse and people said 'that couldn't happen'."
Ms Sdrinis has worked on a case involving a student who was sexually assaulted with an object by another student at a Victorian state school.
Compensation claims against schools are only successful if there is evidence the school knew or should have known students were at risk from a child perpetrator, the director of Angela Sdrinis Legal said.
It follows revelations in The Sunday Age last week that an increasing number of children were sexually abusing other children, with four year olds being referred to programs for problem sexual behaviour.
An Education Department spokesman said the statistic of 41 sexual offences at government and non-government schools during school hours in 2014 was low.
"This figure represents 41 incidents across a student population of about 880,000. While one sexual offence is one too many, such a low rate reflects the work schools do to create safe, supportive environments for all children."
All sexual assaults were taken seriously, he said.
While the Catholic Education Office collects data on sexual assaults in their schools, Independent Schools Victoria does not.
"Independent Schools Victoria takes its obligations to protect children from all forms of abuse very seriously," chief executive Michelle Green said.
A Victoria Police spokeswoman Sara-Jane Hooper hinted the numbers could be higher, saying sexual offences went under-reported.
Carpell Dang from the Centre Against Sexual Assault runs programs in schools that teach students about consent, domestic violence, sexting, pornography and healthy relationships.
Mr Dang is sometimes called into schools after a student had been harassed or sexually assaulted by another student.
"We try and do prevention but sometimes people call us when issues hit the fan."
He said children were being exposed to pornography at a younger age, which was fuelling "extreme stuff".
Sexual offences included in the CSA data include rape, incest and indecent assault. The data is based on information recorded by police.
The figures provided to The Sunday Age do not include incidents of historical sexual abuse reported to police in 2014.
Victoria Legal Aid director civil justice access and equity Kristen Hilton said young people were much more sexually aware now than 20 years ago due to technology.
"But with that doesn't necessarily come a level of sexual maturity."
Legal Aid runs a program in high schools called Sex, Young People and the Law which teaches students about "what a healthy relationship means and the consequences of their actions".
With Chris Vedelago