The Australian Greens have urged Prime Minister Abbott to keep big business out of public education, following reports the Coalition is looking to Americanise Australian schools.

Australian Greens spokesperson for schools Senator Penny Wright said corporations should not be dictating curriculum.

"Our public education system should provide a chance for every student to reach their potential, and no - we don't want fries with that," Senator Wright said.

The Abbott Government cannot say where almost $30 billion in budget cuts to schools will be found, says Australian Greens spokesperson for schools Senator Penny Wright.

Senator Wright said estimates questioning late last night revealed the Government had picked a random number with no thought to the consequences.

"The best Treasury could do was say the cuts to schools would be 'something less than $30 billion'," Senator Wright said.

"When even Treasury doesn't know the real numbers - you know there's no plan behind this policy.

Australian Greens spokesperson for Schools Senator Penny Wright has urged the Coalition to reverse their cruel cuts to Australian schools as businessman David Gonski speaks out.

"If there was ever a time for Tony Abbott to do one last backflip on education - now is it," Senator Penny Wright said.

"This is Australia's future on the line. There can be no age of opportunity while we leave hundreds of thousands of children behind.

South Australian Greens Senators Sarah Hanson-Young and Penny Wright have slammed the Coalition's first budget, which slugs SA families while letting big business off the hook.

"This is a brutal budget by a cruel Coalition," Senator Wright said.

"Not only has Education Minister Christopher Pyne turned his back on SA school students by ripping the heart out of the Gonski reforms, he wants to make it harder and more expensive to go to university.

Tony Abbott's decision to dump the Gonski school funding reforms will disadvantage every one of Australia's 3.6 million students, says Australian Greens spokesperson for schools Senator Penny Wright.

"The Coalition has abandoned every child, every parent, every teacher and every school, but none more so than those in greatest need," Senator Wright said.

"Tony Abbott and Christopher Pyne have turned their backs on equality - wilfully and ruthlessly entrenching privilege in education.

NAPLAN tests should be moved to the start of the year to limit "cramming" sessions and relieve pressure on students, says Australian Greens spokesperson for Schools Senator Penny Wright.

Senator Wright also urged the Government to remove school ranking and comparative functions from the MySchool website, in line with the findings of her Senate inquiry report.

"Moving NAPLAN tests to the beginning of the year would be less disruptive to students and reduce the temptation for excessive coaching sessions," Senator Wright said.

Greens spokesperson for Schools Senator Penny Wright today urged the Abbott Government to release its Curriculum Review draft report, more than a week since it was delivered to Education Minister Christopher Pyne.

"The Abbott Government is intent on pushing its conservative political agenda into the classroom, overturning the work of several years and thousands of submissions which went into the development of the Curriculum," Senator Wright said.

A Senate Inquiry into the NAPLAN tests initiated by Australian Greens spokesperson for Schools has today recommended substantial changes to the tests and the MySchool website.

"The committee heard a huge amount of evidence that the MySchool site has introduced a competitive element which is damaging student and teacher wellbeing and resulting in a whole lot of ‘teaching to the test'," Senator Wright said.

"As a committee we came to the view it's time the ranking and comparative functions for individual schools on the MySchool site were removed.