A former Productivity Commission economist has called for an integrated system of funding government and non-government schools alike.

In a submission to the review of school funding headed by businessman David Gonski, economist Trevor Cobbold, the national convener of public school lobby group Save Our Schools, calls for a complete overhaul of school funding that would end the separate arrangements for public and private schools.


Mr Cobbold proposes a federal schools commission to co-ordinate funding arrangements, and set a baseline funding amount, based on a theoretical benchmark of the resources required to educate the average child to the end of Year 12.


He suggested using as a starting point the resources required to educate a child in a government school in an affluent area, such as Sydney's north shore, where schools receive about $10,000 a student.


On top of the baseline funding, schools - both public and private - would receive "equity funding" to provide additional support to those students falling behind at school, and to groups of disadvantaged students.


The individual equity funding component would provide extra money to schools when more than 5 per cent of students were not achieving at the level required to complete Year 12, and would be weighted according to the social background of the students and the school community.


The social equity funding component would provide extra resources to lift the average results of groups of disadvantaged students to the level of students from high socio-economic backgrounds.


"It's about expecting high standards for all students. There's no reason in principle to assume that indigenous kids are less intelligent than high SES students; it's due to their background," Mr Cobbold said.


"If that's the case, then we should expect average results of students from different groups to be similar. It doesn't mean that everyone's results will be the same, but the average will be similar."


It estimates that an additional $6 billion to $9bn a year is needed to ensure an adequate education to Year 12 for indigenous, remote and low-SES students.