A survey of Christchurch Girls' High School students has uncovered widespread sexual harassment outside the school and 20 cases of rape by individuals or groups.
It revealed 60 percent had been harassed including groping or verbal abuse.
It was said to have happened on public transport or at McDonald's and involved boys from other schools and adult men.
Most respondents did not report the abuse and only 10 percent received any help.
In response the school had hired extra counsellors and brought in police.
Principal Christine O'Neill told Nine to Noon there were many cases where sexual assault and rape were implied but not stated.
"By that I mean something like: 'I had too much to drink and my boyfriend took me to a room at the party to rest. I trusted him but he came back with several of his mates and they did things to me'."
O'Neill said the students had mostly stayed silent and she hoped the survey would help encourage those at other schools to speak out.
She said many were too traumatised to report being raped.
"[I'm] shocked, I guess by the scale and the ubiquitousness of it, saddened that our young people are living their lives in such a limited way like this."
Head girl Amiria Tikao was glad the survey had given the girls a voice.
"We are absolutely sick and tired of these behaviours and we're ready to call them out. I think the girls and all the students at our school have a feeling that this behaviour has been totally normalised and we've come to a point where we're ready to take action."
She knew of girls who had changed the way they dressed or who stopped going to parties in order to avoid the abuse. She was sure the situation faced by girls at her school would be repeated around the country.
"We have to make changes to our lives, the way we look, the places we go in order to manage sexual harassment and it's unacceptable on every single level. And this is things like not wearing skirts that are too short out in public, not being able to go outside after dark by yourself."
O'Neill wants the Education Review Office (ERO) to instigate another survey that would be open to schools around the country.
She said the attitude of boys and men towards girls and women was a systemic issue.
In a statement released late this afternoon, the ERO said it found it deeply concerning that sexual harassment had become "normalised" for young people.
The ERO said it had previously evaluated schools and found sexuality education needed to be more comprehensive and the variability across schools needed to be reduced.
It said it already presented a survey on wellbeing to students to take anonymously nationwide, which was turned into a report. It stressed having important conversations about what respectful and healthy relationships looked like, not only in schools, but as a country, as families, as individuals, in workplaces and as parents.
Call for survey to be done nationwide
National Survivors Advocate Louise Nicholas said the survey needed to be done nationwide in all schools including primary schools.
"I think we need to be stop being so PC [politically correct] about sexual violence prevention, this type of behaviour doesn't just happen to our girls, it also happens to our boys and it also happens to our rainbow youth and those in the LGBT and disability communities."
Nicholas said it was a wider issue that needed to be called out.
A Christchurch MP said she was not surprised by the high incidence of sexual harassment and assault experienced by Christchurch Girls' High school students.
Ilam MP Sarah Pallat said it was consistent with what she knew to be a broader societal problem and the blame lay solely with the perpetrators.
Where to get help:
Victim Support 0800 842 846
Rape Crisis 0800 88 33 00
HELP Call 24/7 (Auckland): 09 623 1700, (Wellington): be 04 801 6655 - 0
Mosaic - Tiaki Tangata Peer support for males who have experienced trauma and sexual abuse: 0800 94 22 94