The report says schools had failed to respond to the change in social and technological context around sexuality in the past 10 years.

Sex education in New Zealand is no better than it was a decade ago - and students are being let down by a lack of education around consent, pornography and sexual violence, a new report shows.

In 2007, the Education Review Office (ERO) found the majority of schools were not effectively meeting students' needs with sex education.

Māori and Pacific students were being particularly let down, as were students with additional needs and students who were sex-, gender- or sexuality-diverse.

A decade later, it's the same story.

Schools have kept their 2007 attitudes towards technology and social media, too.

The report noted in the past decade, "the social and technological context around sexuality and sexuality education has shifted quickly and profoundly".

The quality of schools' sexuality education programmes, however, "has not kept pace with this shift".

Just one fifth of schools included social media and the internet in their sex ed programmes.

Despite high-profile conversations around sexuality and consent, the proliferation of porn and the rise of sexting, sex education has stubbornly revolved around the biology of sex.

Anatomy, physiology and puberty were the most commonly covered topics.

Secondary schools also tended to cover gender stereotypes and diversity in sexuality, but this was seen much less in primary schools.

Sexual violence and pornography was taught by fewer than half of secondary schools.

This is despite students wanting schools to be proactive in educating them about sexuality before social media does, said Dr Deirdre Shaw, ERO's evaluation services group manager.

"Students say they're exposed to sexuality through the media and their peers, but need the knowledge and skills to respond in a healthy way," she said.

Associate professor Dr Katie Fitzpatrick from University of Auckland's Faculty of Education said some teachers "are underprepared and not confident" to address the issues of pornography and sexting with students.

"Teachers have not had the support from the Ministry of Education nor from the Government to access professional development in these areas," Fitzpatrick said.

Associate Education Minister Tracey Martin said she was "deeply saddened" by the lack of improvement in the delivery of sexuality education over the last decade.

"It's disappointing because how students feel about themselves and their relationships and how they keep themselves safe and make well-informed decisions is really important to their wellbeing.

"On top of that some schools are clearly doing it well, so it isn't impossible."

Michael Alexander, a school nurse who has worked in New Zealand and overseas, said ideally sex ed would be taught across three key areas - biology, sexual health and relationships.

"They need the biological side so they understand how conception works, they often don't know the risk factors for their sexual health once they are sexually active and relationships covers off trust and consent," he said.

ERO visited 10 urban schools identified as having good practice in sex education and found they paid attention to the voices of their communities, and recognised "the importance of comprehensive sexuality education in supporting student wellbeing".

Within the report, humour was identified to be a successful way to engage in "awkward conversations" with Māori students.

One teacher, from a large co-ed school with more than 200 Māori students, said in the report: "When you sit down with our kids … it's a serious topic but you can laugh about it too. That makes them more open to talk. The kids really engage with it – they understand they're in a safe place to talk".

At another school, a transgender student credited the school's large and active queer-straight alliance group with making them feel included.

"I wouldn't have come out if it wasn't for [the group]. I could come into the place without explaining myself, which I have to do everywhere else. I wouldn't be happy without having been able to come out," the student said in the report.

ERO also commended a large co-ed secondary school for celebrating diversity by asking students if they had a preferred name or pronoun, and using non-gendered terms, installing gender-neutral toilets, supporting a same-sex couple as the main characters in their student-directed Shakespeare production and holding gender-neutral events at athletics days.

"These schools were proactive, rather than reactive, and did not simply rely on more general policies and practices around inclusion, but took the time and effort to think about how they could send the positive message for sex-, gender- or sexuality-diverse students that they were welcome and cared for," the report said.