Primary age students have been able to view pornography, sexualised animal content, and information about self-harm on school devices - shocking school leaders and leading to calls for far better online blocking technology.
The Ministry of Education contracts the company Network for Learning (N4L) to provide web filters to schools, but N4L says the technology cannot filter specific content within an unblocked website, such as images or videos.
It says that it is the responsibility of platforms like YouTube and Google to monitor, flag and remove content within their sites they classify as inappropriate.
Speaking to RNZ, parenting educator and former high school teacher Holly Brooker said the testing came about by accident.
Brooker said she was speaking to a teacher about YouTube's use in schools - and when asking questions about whether they knew the site was not filtered, the teacher, the principal and the school's IT developer were all unaware.
"I was immediately really concerned understanding how much YouTube is used in schools, in primary schools, for educational purposes and also having a deep understanding of how much harmful content is on YouTube, but there's this massive gap with teachers and principals and IT experts not actually understanding that it's not filtered."
Conducting the testing at the Auckland schools, Brooker said she and a colleague were "really shocked" to discover what students are actually able to access at school - whether it be on a personal or school-issued device.
"The principals themselves were really shocked as well."
Brooker said they used students' devices to search up different types of search terms including around sexual content, suicide, self-harm, violence and gang fights.
"We just went through a whole different bunch of search terms and we checked out the safety settings that were set on Google and DuckDuckGo, on YouTube, we checked whether social media sites were able to be accessed in primary school, and in many cases they were, so we just took screenshots."
Brooker said N4L put out its own report which showed there had been millions of searches for content around pornography that have been blocked - but more nuance terms have not been. This meant students were able to access it at school.
She said her biggest concern was the "real gap" between educators understanding about what is going on in their classrooms. Brooker said they could not be expected to understand all the tech as they were not experts, but conversations were needed with schools around that lack of awareness.
In one case, Brooker said the school was so concerned by the findings that it took away all the students' devices until the issue had been resolved.
The filtering N4L provided for the government appeared to be of a "very low standard", Brooker said, and some schools were taking matters into their own hands and paying for additional services for more robust filtering.
But there was the argument around the fact that if the government is funding such a service, why should schools have to pay more for it to be better, she said.
The government should be offering "robust, filtered" internet to students aged between 5 and 10, she said.
Brooker said she wanted to see the government "raise the bar" when it came to safe internet for students.
Paying extra for better filtering
One school that pays $5000 a year to have better restrictions in place for its students' internet use if Newmarket School.
Principal Wendy Kofoed told RNZ the school was a "long-term" user of IT and it had seen just how clever and innately curious its students were, and the risks they would take to try and find particular information on sites.
"So we've constantly put in more and more levels of protection for them.
"It's really complex work and involves a lot of education with parents."
Kofoed said the school used LineWize in addition to what the government funded.
As a result, she received a high level of information about what students were searching on the internet and received real-time notifications if anything was searched that should not be.
This helped to know who was searching what, and be able to act on it straight away.
In a recent example, Kofoed said a student had searched terms relating to bullying. With concern the student made be being bullied, Kofoed had a conversation with the teacher and discovered the student was doing a speech on bullying.
But in another example, a student was attempting to search for Roblox, which created a notification to Kofoed, and a second notification when the next search was 'PHUCK' - which related to a song used in Roblox, she said. The searches were blocked, given the adult content, but Kofoed was made aware the searches were happening.
Kofoed said she was grateful for the high level structural support given by the Ministry of Education but said it did not have all the answers.