Police visited the school on Tuesday to speak to students at each year level about safe reporting.
Three girls have since laid formal complaints with police about their experiences.
Christchurch Boys' High School principal Nic Hill said the school actively encourages discussions around diversity and inclusion in the community.
"The school has been working incredibly hard with our students and community to talk about, take action on and lead on the issues of female safety," he said.
"Our senior boys, in particular, have shown strong leadership in this area and we will continue to support efforts to in calling attention to, and stopping behaviours and actions that work against diversity and inclusion."
"While we haven't undertaken any such formal survey within our context, we engage our students in various programmes that educate and empower them on the subject of sexual harassment," she said.
"We also have dedicated pastoral care staff, as well as professional counsellors available to our students at all times for support in all aspects of their lives."
The sentiment was echoed by Rangi Ruru Girls' School principal Dr Sandra Hastie.
"We are saddened but unsurprised by the survey results released yesterday," she said.
"We acknowledge the bravery and honesty of the students taking part in the survey, and support and commend Christchurch Girls' High School for nurturing their students' welfare."
Ministry of Education deputy secretary sector enablement and support Helen Hurst told the Herald school boards must have policies and procedures in place to provide a safe physical and emotional environment for their students.
"This includes having child protection policies that support a strong culture of protection for all children and young people.
"Schools also need clear channels for students who want to raise concerns or report behaviour in a protected environment. There are trusted adults that students can talk to; a school guidance team is just one of the many safe places they can go," she said.
Hurst said when the ministry is aware of concerns about student safety or wellbeing it will contact the school and is available to help coordinate support with other agencies if needed.
"If a parent has any concerns about the safety and wellbeing of their child as a result of behaviours happening either at school or outside of school they should contact the school immediately.
"We encourage anyone that wants to speak with police to contact them directly."
The first national Youth Health and Wellbeing survey WhatAboutMe? is being delivered by the Ministry of Social Development to around 14,000 young people aged between 13 and 18 (Years 9 to 13).
Questions cover a range of topics such as physical exercise, sense of safety at school, in relationships, and belonging in community.
It will also cover sensitive topics such as self-harm, pornography, consensual sexual activity, unwanted sexual contact and where young people go for advice/help about sex and relationships.
Data from the survey is expected to be available in the first half of next year.
"We look forward to working with MSD and other relevant agencies to understand what young people are experiencing and how we, alongside the wider community, can better support their wellbeing," said MoE deputy secretary early learning and student achievement Ellen MacGregor-Reid.
Where to get help:
• If it's an emergency and you feel that you or someone else is at risk, call 111.
• If you've ever experienced sexual assault or abuse and need to talk to someone call the confidential crisis helpline Safe to Talk on: 0800 044 334 or text 4334.
• Alternatively contact your local police station.
• If you have been abused, remember it's not your fault.
