Public schools will be almost $2.7 billion worse off due to the Abbott government's decision to not fund the final two years of the Gonski agreement, according to a report prepared for the Australian Education Union.
The Coalition scrapped the final two years of the original six-year needs-based funding agreement, which were to deliver the bulk of the money. Instead, only the first four years of the model will be supported, with funds indexed to inflation from 2018.
The report, written by former government policy adviser Jim McMorrow, found government schools would receive $2.67 billion less in 2018-19 and 2019-20 than they would have received under the former agreement, while privates schools will lose $1.2 billion.
The figures take into account the winding down of the National Partnerships scheme in schools.
NSW Teachers Federation regional organiser Nicole Calnan said the new arrangement meant Gonski payments would essentially replace those formerly provided under the National Partnerships model, nullifying the purpose of the agreement and disadvantaging students.
"The Gonski funding model was about funding all schools on the basis of the needs of their students, and the Abbott government's decision to end that funding means gaps between schools will widen in the future," she said.
However, a spokesman for federal Education Minister Christopher Pyne said those projections were wrong and that there were no figures in the federal budget that supported the "wild claims".
"The Australian Education Union wheel out the same dodgy report every second month, add a slap of lipstick and pretend it's new," he said.
"Australia spends more per student on school funding than Finland, yet our outcomes have been in freefall. We need to refocus on what really matters in the classroom."
He said the Coalition had delivered $64.5 billion for schools, which increases over four years.