Schoolchildren in wealthy areas have abandoned tuckshops in great numbers as junk food is removed from the menu, sales figures from a major vendor suggest.
New requirements for schools ensure that any food and drink they sell are "healthy options".
The guidelines - which came into effect this week - divided respondents on an nzherald.co.nz message board, with some saying they were a good idea and others claiming they just pushed students to go elsewhere to buy high-fat and high-sugar foods.
"The apples are given away free with every purchase and are thrown around the playground rather than eaten," wrote a teacher from Pt England.
Figures from catering company Spotless - which provides food at about 90 schools, including 20 where it runs tuckshops - show sales dropped by about 20 per cent in schools in wealthy areas as unhealthy food was phased out last year.
But the company's food services general manager, John Wilkinson, said sales were virtually unchanged at schools in lower socio-economic areas and had since grown.
Mr Wilkinson said food bought at canteens in wealthy areas was often a "treat", so sales were harder hit when chips, carbonated drinks and chocolate bars went. Introducing new products since then saw sales in schools with the biggest drops recover by about 15 per cent, he said.
"The key to our recovery is to introduce popular alternatives and work with our school clients at improving the nutritional education."
Generation Foods director Sharon Main said the company - which provides food at about 200 Auckland schools, including 40 where it runs tuckshops - noted the same trend.
"They [students in wealthier areas] never spent a great deal of money anyway but, yes, it has dropped off."
Ms Main estimated student numbers at some canteens had halved. "They all go to the dairies instead."
Robin Staples, director of Southern Cross Campus in Mangere, was surprised by the sales figures.
He said that for many of the decile 1 school's students, buying lunch was about meeting "basic requirements" and they wanted the best value for money. "One of the problems we've got is we are competing with $1 pies through the local dairy," Mr Staples said.
"We have a bit of an issue with the quality of food being sold on the way to school and on the way home."
He said the school would next week advertise to re-tender its canteen after reshaping specifications to meet healthy eating requirements.
"It's really not our core business of learning and teaching, but inevitably there's some responsibility to make sure we do offer healthy food."
Mr Staples said canteens played an important role because bringing lunch from home was an idea from the "distant past" for many children.
"It's the way a lot of our families are now living - there's a lot of kids now who don't even know what a cut lunch is.
"We've gone from a phase of having that most of the time and the odd Friday treat, to now it being most of the time bought and the odd time where you have to bring something from home."
The Education Review Office will monitor schools' compliance with the guideline in three-yearly reviews.
A spokeswoman said boards of trustees' planning had been evaluated in reviews held over the past six months and was being analysed.
PUPILS CAN NO LONGER BIFF UNEATEN LUNCH IN BIN
A Manukau City school this week joined the growing number that require children to take home their uneaten lunch.
Alfriston acting principal Carole Crompton said the benefits included cutting rubbish on site and helping parents to see what their children were not eating.
"If my child has still got sandwiches in his lunchbox after school, then that's what he has for afternoon tea on the way home. He's quite happy to - it's not that he doesn't want them, he's been too busy playing," said Ms Crompton.
"Over the course of the day, you know they've had all the things you've chosen them to have."
The new rule came into force at the school this week. Common items that used to end up in the bin included fruit "with one bite taken out" and sandwiches still wrapped.
Ms Crompton said there had been no complaints about the new system and it was a growing trend already in use at several schools nearby.
She said pupils had little option but to comply as rubbish bins remained in classes but had been removed from the grounds.
The school's worm farm had not missed out, she said.
Leftovers from teachers' lunches had so far provided enough to keep the worms going.