At all of these schools, parents paid on average $1,800 a student, according to data from the national education and curriculum authority

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Many parents with children in public school are paying thousands of dollars a year in fees and contributions at levels rivalling the compulsory fees paid to attend some private schools, leading to concerns the principle of a free, government-funded education is being undermined.

At the 50 public schools where parents paid the most in fees and contributions, parents paid an average of more than $1,800 a student, an analysis of the latest funding data from the Australian Curriculum, Assessment and Reporting Authority, provided to Guardian Australia by the Greens, reveals.

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