The teachers' union has been accused of "misrepresenting data" to back up its contention that Catholic schools rake in more government support than public schools.
Australian Education Union (AEU) analysis of the latest ACARA 'My School' data revealed students at independent and Catholic schools in the Gilmore electorate were $1780 and $1652 better off than those in public schools.
The analysis found independent schools in Gilmore receive 12 per cent more Net Recurrent Income [for ongoing operating costs of schools] per student than public schools, while Catholic schools in Gilmore receive 12.9 per cent more per student than public schools.
NSW Teachers Federation president Maurie Mulheron said the figures highlighted the urgent need for fairer funding arrangements for public schools.
But a spokesman for the National Catholic Education Commission said the AEU was "deliberately misrepresenting funding data".
"All students are funded according to need and according to the same formula, regardless of sector," he said.
"The only difference - and it is a key difference - is that non-government schools have their needs funding reduced according to their parents' ability to pay fees.
"This reduction doesn't happen in public schools. For this reason, non-government schools cannot attract more government funding than a similar-sized government school with similar student needs."
Minister for Education Dan Tehan agreed, adding "this shonky analysis has already been exposed as "misleading" by independent experts quoted in today's newspapers".
"Labor should be ashamed unions are spreading lies on their behalf," he said.
But the AEU, who have been actively campaigning against the Coalition's re-election, said the data highlighted the "deep funding inequality facing public schools."
"When independent and Catholic schools in Gilmore are receiving that much more funding than public schools you know how unfair the system has become," Mr Mulheron said.
"Despite growing enrolments in public schools in Gilmore compared to private schools, the Morrison Government has handed billions of dollars of extra funding to private schools while cutting $14 billion from public school funding.
"The only way to start levelling the playing field is to restore the federal funding that public schools should have received this year and last year. Thankfully, Labor has made a commitment to do exactly that if it is elected....and will boost funding to public schools in Gilmore by additional $21.6 million in the first three years."