Kaipara Flats School principal Debbie Hamer said her school asked for a review of its decile in 2019 and moved from decile 9 to 4.
"We made sure we contacted every single parent, all the whānau in the area, to get a response from every family. We filled in the forms and we sent them off and I thought to be honest that we'd probably go down one or two deciles so when it came through decile 9 to decile 4, I was really shocked," she said.
The change was worth a lot of money for a small school and it was probably time to review the system, Hamer said.
"I'm sure there are lots of schools sitting out there with a historic decile rating that they've never challenged or didn't know they could challenge."
It took a lot of effort to ensure the school's review application included information from all families and that would be a lot harder to do in larger schools, she said.
Oropi School principal Andrew King said it moved from decile 9 to 8 after a review, but some families did not provide information.
"My hunch is that a true indication of our actual decile would be a 6 or a 7, not an 8, but that would have required more survey information from a greater number of families in the community," he said.
King said changing from 9 to 8 brought the school about $8000 a year in decile funding and he estimated it would get double that figure if it moved to decile 6 or 7.
Omokoroa Number One School principal Craig Pentecost said his school's decile review in late 2020 failed altogether.
He was confident the Bay of Plenty's school's decile would change if the numbers were recalculated using up-to-date information, but he'd rather dump the system altogether.
"Decile 10 status is not a true reflection of our learning community," he said.
Pentecost said it would be exciting to see the equity index in this month's Budget.
The index was developed several years ago and was based on data about individual children at each school, rather than the neighbourhoods they came from.
The government had planned to introduce it this year but Covid-19 interfered, however, last year's Budget included $23 million to introduce it by 2023.
'A lot of complexity'
But Te Pohue School principal Richard Gillespie said he was not keen.
He said the government used the index to decide which schools would get free lunches, and decile 2 Te Pohue missed out even though a significant proportion of children were from disadvantaged backgrounds.
"With the equity index, according to the list of characteristics and how it's created or where we sit, we can't see how our numbers are the way that the ministry see them and line up. All the stats and the info that we've got here don't line up with the position they say we're in," he said.
Secondary Principals Association president Vaughan Couillault said moving from deciles to the index would not be easy because the numbers were used for more than just allocating extra money to some schools.
"There's quite a lot of complexity in terms of what a decile number is used for outside of that targeted funding in terms of the wider sector. Even as far down and granularly as principals' salaries. There's a component of a principal's salary that is tagged to the decile of the school."
But where the index had already been used, such as for selecting schools for free lunches, it seemed to have worked reasonably well, he said.
"The deployment of the equity index across varying support mechanisms in recent years hasn't had an allergic reaction to it, so it seems to be landing well."
Couillault said decile numbers were becoming "vintage" and some schools' numbers would no longer reflect their community.
It is not yet clear what the government is doing with the index, but Minister of Education Chris Hipkins said it had not been abandoned.
