Government funding for state and state-integrated primary and secondary schools decreased last year by nearly $150 per student, according to new figures from the Ministry of Education.
The records show the average spend per student in 2014 was $7,194.71, which fell to $7,046.11 last year.
Adjusted for inflation, Parliament's library calculates the drop is $192 in real terms.
The per student amount includes funding for property, operations and salaries, and is averaged out over all years of schooling from years 1-13.
Property funding is the main reason for the drop and with it excluded, the per-head funding actually increases by around $50, or $20 in real, inflation-adjusted terms.
Education Minister Hekia Parata vehemently rejects there's been a decrease, pointing out that cash has been pumped into her portfolio every year since National took office.
"All schools are funded by the Government. All of them, except for private schools, have had increases.
"If you're asking if funding for education has gone down, the answer in no. It's gone up every year since we've been in Government," says Ms Parata.
Labour's Chris Hipkins isn't buying Ms Parata's explanation, saying parents are having the shortfall passed on to them through higher fees and demands for bigger school donations.
"We've seen costs that parents face increase at 10 times the rate of inflation over the past couple of years.
"The simple reality is schooling is no longer free for kids in New Zealand. This is something Bill English decried when in opposition and since he's been in Government, he's made the problem worse," Mr Hipkins says.
A spokesperson from Ms Parata's office says the decrease in property funding was due to a drop off in demand and not as many schools needing work done as the previous year, pointing to new schools being built in Christchurch.
Mr Hipkins rejects that explanation, saying hundreds of schools across the country require property expenditure and doubts any of them would turn down funding.