Principals say it's "party time" in many Auckland schools because the city's housing shortage has bumped about half the region's schools down the decile ratings - winning them extra state funding.
Official figures, recalculated based on last year's Census, show 50 per cent of schools in the Auckland South district, which includes the former Auckland City, Manukau, Papakura and Franklin council areas, have dropped at least one step on the decile scale. Forty per cent of schools in Auckland North (North Shore, Waitakere and Rodney) also dropped, picking up extra state funding of up to $70,000 a year per school for special education, books and other discretionary items.
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The main driver of the changes appears to be household overcrowding fuelled by record net immigration at a time when home-building has been depressed because of slow growth.
But the changes have also pushed schools in areas of static or declining population, such as Gisborne and Southland, up the decile rankings, meaning parents may face additional requests for funding assistance.
Auckland Primary Principals Association president Deidre Alderson, whose 800-pupil Willowbank School in Dannemora has gained about $13,000 a year by a downgrade from decile 9 to decile 8, said the extra money would go into programmes for gifted students and children with learning difficulties. She said the money would be more welcome in lower-decile communities.
"For some schools it's a little bit of a party, I would say," she said.
But Carmen Edwards, principal of tiny 28-student Patutahi School near Gisborne, said a lift in her school's rating from decile 1 to 3 would be catastrophic if allowed to stand. She has not worked out how much funding she might lose, but said, "It's going to be a lot, even if it's only a few thousand, because we don't get very much.
"We use it just for the basics," she said. "We provide stationery because the families can't afford it. We don't have school fees because there's no way they'd get paid."
More than 90 per cent of her students' parents were on benefits, and she would appeal against the new decile rating as she did after the last two Censuses in 2001 and 2006.
The decile ratings give equal weight to five factors: household income, occupations, educational qualifications, overcrowding and the proportion of people on benefits.
Despite Auckland's economic growth, the region's rapid population growth between 2006 and 2013 meant its median personal income dropped from $26,800 to $25,170 when adjusted for inflation.
Ms Alderson said overcrowding had also become an Auckland phenomenon, driving the decile change, and parents' disposable income may not be as great as in other areas. "We might have one of the highest market values of housing, but our parental occupations or incomes are possibly still lower, so the disposable income in this area may not be as great as in other parts of New Zealand."
Ms Alderson said that apart from direct funding, the decile ratings also affected programmes such as fruit in schools, social workers in schools, Duffy Books and Kidscan food supplements which were all targeted at low-decile schools.
Kidscan chief executive Julie Chapman said her food and clothing programmes were aimed at deciles 1 to 4, but she promised to keep serving any schools that already received them and moved to higher deciles. The agency was already feeding close to 15,000 children a week.
Ellerslie School, in the Auckland South area, has gone from decile 7 to 9. Principal Chris Magner said the rise was more of a curse than a blessing. "It means $25,000 less to balance the books. It's my job to make sure the children's learning doesn't suffer " and it won't. It's a bit of a hit but we'll plod on."
Education Minister Hekia Parata has given schools $8.6 million to adjust to decile changes over the next 18 months. She has also hinted at a review of the funding system "to make sure it is correctly targeting the students who need it most".
Two-point rise 'reflects house prices'
Auckland mother Sanchia Logie says a jump of two decile places for her daughter's Pt Chevalier school likely reflects the change in socio-economic status of local residents.
Ms Logie and her husband Brent Bielby have lived in the suburb for about 11 years.
The couple's 9-year-old daughter Lily Bielby is in Year 5 at the decile 10 Pt Chevalier School. Their son Callum Bielby, 12, a former pupil, goes to Ponsonby Intermediate, which is decile 9.
"It certainly reflects the change in house prices here," Ms Logie, a child psychologist, said of Pt Chevalier School's increased decile rating.
"People are obviously more well-off. More people now are knocking houses down and building right from scratch. I think when that sort of thing starts to happen, it's showing there is more wealth in the area," she said.
"I think even to buy into Pt Chev, it's starting to be more and more limited to families that can afford that," she said.
Receiving less Government funding would be a blow for Pt Chevalier School, but most in the community would be well-placed to deal with it, she said.
"I think some lower decile areas might struggle more with something like that," she said.
"Although it is hard with parents having to contribute more, I do think it is representative of changes in the area.
"Obviously it's going to be a big hit to the community and hit to the school in terms of what they can give the kids."
However, the school had a lot of support in the community, she said.
"Pt Chev is a really good school community, we got together and had an enormous school fair and made quite a lot of money ... something like $70,000."
Q & A
What is the decile system?
The decile system ranks schools by the socio-economic status of the areas where their families live. It allocates about 11 per cent of school operational funding (excluding salaries), giving more to schools in poorer areas.
How does it work?
Deciles are based on household incomes, occupations, educational qualifications, overcrowding and the proportion of people on benefits in a defined area where pupils live.