By political reporters Anna Henderson and Francis Keany.
The national teachers union has accused the Prime Minister of abrogating his responsibility to public schools by suggesting the states take responsibility for funding them.
The proposal, which doesn't include any hard numbers, has received a lukewarm reception from the states ahead of Friday's Council of Australian Governments (COAG) meeting.
The Prime Minister originally raised the proposal as a way for the states to directly fund hospitals, and this morning he said it was also possible to make a "very powerful case" for the states to take over full responsibility for public school funding.
"They (states) would then have the responsibility for state schools, which are the schools that they manage, they have the resources as well," he said.
Treasurer Scott Morrison told the ABC the funding proposal would only be put in place if all states agreed.
"That would only occur a) if all agreed to it and b) they would have all funding that they would have going forward for funding those schools as part of their income tax revenue," he said.
"The states would be in a position to completely fund that, in the same way that they fund police stations and jails and things like this.
"No-one sits around in the states and territories and says 'the state treasurer needs to go to the federal treasurer and ask for more money to run our police stations'."
The Australian Education Union has blasted the proposal and is particularly incensed by Mr Turnbull's confirmation the Federal Government would continue to fund private and independent schools regardless.
The union's deputy president Maurie Mulheron described the move as a "betrayal" for parents and students in the state school system.
"The PM is abrogating that responsibility and rejecting a model that has already addressed those concerns," he said.
"This is a return to the bad old days where the Commonwealth gave money to private schools and the states were left to try to find money for the state system."
It's a view echoed by federal Labor with Opposition Leader Bill Shorten accusing Mr Turnbull of dumping schools "in the lap of the states" and abandoning students.
States wary of tax plan and lack of detail
Queensland's leader Annastacia Palaszczuk said it was "not acceptable" for Mr Turnbull to raise the proposal publicly without explaining it.
"I look forward to the lecture that we'll be receiving from the Prime Minister tomorrow," she said.
Victoria's Premier Daniel Andrews has been questioning the logic of the proposal, in particular the Prime Minister's claim that the total tax take will not rise.
Smaller states like Tasmania expect to be worse off under the plan, despite Mr Turnbull's assurances, and Premier Will Hodgman has described it as a "race to the bottom" proposal.
Northern Territory leader Adam Giles said he had calculated the cost to taxpayers in his jurisdiction and they would be worse off under the proposal. He also noted the lack of detail ahead of tomorrow's meeting.
"This is politics, it's an election year, there's a bit of brinkmanship and chest-beating going on," Mr Giles said.
He questioned whether the push to consider income tax changes was designed to bring the states back to the bargaining table on potential changes to the Goods and Services Tax.
WA Premier says some states are penny pinching
West Australian Premier Colin Barnett said Mr Turnbull's proposal was on the right track, and handing control of public schools to the states was a sensible idea.
"It seems to me that the other states are just getting down to the sort of penny pinching, 'How many dollars in it for me? How many do they get?'," he said,
"This is a chance to have a high level discussion about having a better matching of revenue raising and revenue spending."
Earlier this week ACT Chief Minister Andrew Barr was also positive about the general income tax proposal, describing it as a measure worth considering.
South Australian Premier Jay Weatherill said he would approach tomorrow's discussions constructively but the income tax proposal in its existing form was "unworkable".
Mr Weatherill has previously advocated for the states to get a share of income tax, but through a different formula.
New South Wales Premier Mike Baird said he wanted to see more information before passing judgement.
This post originally appeared on ABC News.
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