If Flemington School's decile rating remained at 10, there would be less funding for important aspects of school life, Mr Bourke said.
"We'd have to relook at the budget and look at where funds go. Focusing funds in some areas would mean having to trim them back in others."
Rotorua Seventh-day Adventist School principal Lanea Strickland was likewise bewildered by the school's decile jump. It rose from decile 3 to decile 6.
"We're state integrated, so a lot of our students travel from outside the area [the ministry] do their data gathering from," she said. "When we looked at the area taken into consideration, we found that there was only one family living in it."
The principals of St Michael's Catholic School in Rotorua and Fenrdige School in Masterton also told NZME. News Service they had sought a review.
The decile ratings were calculated by using student address information, combined with Census data for small geographical areas.
The ministry refused to release the names of the schools which have challenged the ratings but said schools would know the outcome by the end of May when the decile ratings for all schools will be updated on the ministry website.
Education Minister Hekia Parata has previously said the decile funding system was well-intentioned but also complicated and "really clumsy"
"There are some significantly disadvantaged kids and families in deciles seven, eight, nine and 10 schools, but overall the average masks that," she said. The decile system, also described by Ms Parata as a "blunt instrument", has been readdressed as part of a wider review of school funding.
Schools whose funding was cut after moving to a higher decile would have an 18-month transition period and additional funding to assist them, Ms Parata said.
"There are many factors that make a good school good and it's important to remember that decile funding only accounts for about 12 per cent of overall funding for schools.
"Decile ranking shouldn't be used as a measure of school quality or school performance."
