Several inner-city schools have raised concerns about parties for young teens being held at some commercial nightclubs in Dunedin.
One such - a foam party for year 10 and 11 pupils - in particular has been criticised by principals.
Otago Boys' High School pupils have been sent home with a newsletter warning there are two groups organising large social/dance party events for secondary school pupils in Dunedin, and tickets for one of the events had been sold by an organiser on the street outside the school.
"Parents should be aware that these events are not connected with the school in any way, and we do not endorse them," the newsletter read.
"Some boys have attended these events without their parents' knowledge and we encourage parents to be vigilant about where their sons are spending their time."
Otago Boys' High School rector Clive Rennie said his concerns were for the security and safety of pupils.
"It would appear there's an accessibility to alcohol before the event and we would question some of the themes at these parties.
"Is it appropriate to hold a function where 14- and 15-year-olds are squirted with foam while wearing white T-shirts?"
The school was always happy to work with groups that had the interests and recreation of pupils at heart, Mr Rennie said.
"But these people have never contacted us.
"We don't know enough about these parties. They are targeting school pupils but they are not working with us.
"I would presume the same thing is happening in other schools in Dunedin as well. I would be surprised if it's not."
Kavanagh College principal Tracy O'Brien, St Hilda's Collegiate School principal Melissa Bell and Otago Girls' High School deputy principal Jock Murley shared his concerns.
"It's entirely inappropriate. Surely we can come up with some other means of celebrating," Mr O'Brien said.
"It sounds like lewd behaviour."
The foam party has been organised by photographer and dancer Daniel Chew and will be held at the Break, in Dunedin.
Mr Chew said he had sold tickets to the event outside Otago Boys' High School, but said it was a one-off, because he knew three boys at the school who wanted to buy tickets.
He said teens would be wearing fluoro-coloured T-shirts, not white, and there would be plenty of roaming security at the event.
He believed the event would provide a safer party environment than someone's private home where alcohol might not be tightly controlled.
The Break owner Jono Kennedy said parties for young teens had been held at the venue once a term for the past year.
No alcohol was supplied, but security was, he said.
"The event introduces them to the nightclub scene in a safe and secure environment. We're not trying to groom them."
Mr Kennedy was not aware tickets were being sold outside school premises, but was comfortable with the practice.
He said pupils had been canvassed about what kind of party they wanted to attend and the majority had requested a foam party.
"So that's what we're giving them. There's nothing suspicious about the whole thing.
"We've had some good responses from parents about our parties," he said.
Dunedin Police Youth and Community Services Senior Sergeant Mark Crawford said the function was private, no alcohol was involved and there was little the police could do to stop it.
"Parents need to know where their kids are going, and make choices about whether they be allowed to go or not, based on their own assessments of the function."