The political battle over the Gonski funding model for lifting educational disadvantage is being taken to the streets.

Key points: Australian Education Union President says needy schools will miss out on $3.8 billion in 2018 and 2019

Australian Education Union President says needy schools will miss out on $3.8 billion in 2018 and 2019 Education Minister Simon Birmingham has disputed the AEU's claims and called the national schools tour a "scare campaign"

Education Minister Simon Birmingham has disputed the AEU's claims and called the national schools tour a "scare campaign" Deputy leader Tanya Plibersek says the Government will deliver a "$30b cut to education"

The national education union is setting off on a bus tour across the country in a bid to save the controversial plan, protesting what it says are rollbacks to the Gonski funding model.

Businessman David Gonski proposed a series of reforms designed to level the playing field between privileged and disadvantaged students.

The model directs extra funding towards schools with high numbers of students of low socio-economic background and has been used by schools to fund specialist teachers and literacy programs.

The schools are located across the country and hundreds have already received boosted funding.

But the Australian Education Union (AEU) has warned the Gonski model is under imminent threat.

The Federal Government has indicated it will roll out a new funding model from 2018 that will be tied to school reform, in particular teaching standards and effectiveness.

AEU President Correna Haythorpe claimed needy schools would miss out on $3.8 billion in 2018 and 2019.

"The Government is ignoring the evidence that's in front of it now that this Gonski funding is changing lives in our schools," Ms Haythorpe said.

"Our question to Malcolm Turnbull is which child is he going to leave behind by not implementing this funding beyond 2017?"

AEU Campaign is 'disingenuous': Coalition

A union bus tour of schools across Queensland, NSW, Victoria and South Australia kicks off today with hundreds of teachers expected to take part. The tour will finish in Canberra on March 22. The union is also planning a national advertising blitz.

The Federal Government has denied any plans to cut funding to needy schools and said it planned to increase funding. It has labelled the AEU campaign disingenuous, and insisted funding would continue to be allocated according to need.

Federal Education Minister Simon Birmingham said the Government had drafted a comprehensive policy — known as Quality Schools, Quality Outcomes — that aimed to lift teacher performance and provide better support to students.

"Contrary to the scare campaign being peddled on schools funding by Labor and the union, the Turnbull Government's Quality Schools, Quality Outcomes policy will deliver record funding to schools that is needs-based and tied to evidence-based initiatives that will lift outcomes for Australia's children," Senator Birmingham said.

"There are no funding cuts. Simply, schools funding under the Turnbull Government will grow from already-record levels.

"The Turnbull Government is growing investment in schools from $16 billion in 2016 to $20.1 billion in 2020, on top of more than $14 billion the Coalition has been delivering for regional and remote schools since we came to office in 2013.

"That is funding above inflation and above enrolment growth projections."

'Complete nonsense': Plibersek

Deputy Labor leader Tanya Plibersek, who also holds the shadow education portfolio, disputed this.

"The Government's position is complete nonsense. Their own budget papers show a $30 billion cut to education," she said.

"We know that even the small amount of extra funding that's already flowed to needy schools has made a difference. I see it in every school I visit. The principal, the teachers, the parents, even the kids can tell you the difference it's made.

"Not finishing the job, not providing these last two years of extra funding, and then beyond that, would be a tragedy."

'Give our kids the best opportunity'

School principal Rob Shepherd is a big supporter of the Gonski funding model. ( ABC News: Natasha Robinson )

At Le Fevre High School at Semaphore South in the Port Adelaide region, principal Rob Shepherd said he supported the education union's Gonski campaign.

Mr Shepherd has seen the impact Gonski funding has had on his students first-hand; he received money to roll out special programs for students who were struggling with attendance and literary and numeracy.

In 2018 and 2019 that funding was due to be ramped up to several hundred thousand dollars.

"The Gonski funding's been really important," Mr Shepherd said.

"Without that level of funding there are students who fall through the cracks. And the last thing that we want to see is a disenfranchised underclass in Australia.

"Australia has prided itself on giving everyone a fair go and the Gonski funding to me exemplifies that really well. We don't all start on the same starting blocks.

"The role of education is to try and give every person in our country the best opportunity possible."