Parents paid more than $61 million in public school fees last year, the latest figures from the NSW Department of Education reveal, but the state government has ruled out means-testing public education and vowed that it will "always be free" in NSW.

On Monday, the NSW education minister Adrian Piccoli fired back at his colleagues in Canberra after Fairfax Media revealed a radical federal government green paper that suggested public schooling could be means-tested and wealthy parents forced to pay for public education.

"The NSW Government will not introduce means-testing for public schools," a spokeswoman for Mr Piccoli said.

Premier Mike Baird also added his voice to the debate on Monday, announcing on Twitter that public education would always be free under the Baird government. 

In NSW, public education will always be free under any government I lead. #nswpol— Mike Baird (@mikebairdMP) June 22, 2015

The education department says principals can request "voluntary general contributions" but parents do not have to pay the fees.

An analysis of the NSW figures shows that parents of children in wealthy suburbs and at selective schools are already paying significantly for a public education, with some parents contributing more than $1400 in school fees per student last year.

According to My School data, parents at James Ruse Agricultural High in Carlingford, the state's top performing school, contributed 18 per cent of the school's total income of $2 million in 2013, including a "general school contribution" of $400, a $500 building fund contribution as well as other subject fees. Up to 85 per cent of James Ruse students come from the top income bracket.

At Sydney Boys High, parents are asked to pay an annual fee of $910 for students in the junior school and $955 for the senior school, as well as a sports levy ($115), a technology levy ($225) a "student research and resources fund" contribution of $160, according to its most recent annual report.

At the non-selective Killara High School, on the north shore, parents contributed  more than $360,000 to the school in 2014. At Punchbowl Boys High School in Sydney's south west, parents contributed a total of $9000.

Schools in disadvantaged areas, where parental contributions make up less than 3 per cent of the schools' total income, are among those that stand to benefit the most from Gonski reforms, according to the NSW Teachers' Federation.

The confidential green paper revealed by Fairfax Media highlighted the federal government's shift away from the Gonksi reforms with the idea that the government could kill off federal funding for public schools, leaving the states $2 billion a year worse off.

A spokeswoman for Mr Piccoli said NSW remained committed to needs based Gonski funding, emphasising the difference between state and federal colleagues on the issue of funding public schools.

"We are funding our six years of Gonski and continue to urge the Commonwealth to do the same," she said. 

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