"Our job is hard enough with our community's socio-economic situation. It's not our kids' fault, we should have sufficient funding to do our job. The system is flawed."
A parent having a tertiary qualification could skew the decile rankings because this was seen as having the ability to go earn a living, Mr Reid said.
Addresses could also affect decile and as many families lived rurally, it may have been assumed that these people were better off than they actually were.
There are five things that influence the ratings: Household income, occupation, household crowding, parent's qualifications and income support.
"For household income, we have only two parents that actually have jobs and the rest are on some sort of income support. Household crowding - we've got a family of 10 living in a three-bedroom house and another family of eight living in a two-bedroom home. One family is living in a camping ground."
To get the new decile changed, Mr Reid has to fill out lots of paper work and has to get the school's parents to give detailed information about their incomes and living situations.
The new round of funding starts on July 15 next year, so changes to a school's decile would not come into effect for eight months.
Mr Reid said he hoped to have all the paperwork ready to go by the end of this term.