This week, Wellington College students were found to have posted comments in a closed Facebook group, saying "f*** women" and "If you don't take advantage of a drunk girl, you're not a true Wc [Wellington College] boy."
Netsafe Outreach director Sean Lyons said as technology use by students continued to be encouraged in schools, there was an increasing need for education on what was appropriate use of said technology.
"There are a lot of high definition cameras floating around in the pockets of students," Lyons said.
Since Netsafe began in 1988, they had seen numerous instances of students using technology to do similar things, he said.
Students would make audio recordings of teachers, or would wind up the teacher then film them getting angry.
"The trick here, I suppose, is to make sure that everybody understands what appropriate behaviour looks like."
This was a job not just for schools, but for parents as well.
"You're talking about young people, male and female, at the beginning of their journey to understand their own sexual identity, their own place among their peers.
"Putting technology in the hands of people at that stage is likely for some to make them behave in a way that's inappropriate.
"If somebody makes sexual gesticulations behind a teacher for the amusement of their classmates, yes, it's still offensive, it's likely to be hurtful if the person sees, it's likely to cause confusion for other kids in the class, but that comes and goes in a moment."
If it was to be filmed, that could be "more distressing" and harmful to the target, but would also provide an opportunity for the perpetrator to be taught a lesson.