GLENWOOD High School marked National Gonski Week with a political push for an additional two years of funding under the needs-based model introduced this year.
Greenway MP Michelle Rowland and Opposition Leader Bill Shorten visited the school of 1561 students on Thursday.
They said schools in the electorate would loose $220 million over the next 10 years if the government did not commit to years five and six of Gonski funding.
"Every student in Greenway will get $1000 less support every year," Ms Rowland said.
"Our teachers want to be working to improve our schools, not spending their time and energy planning for how they will cope with these cuts."
The Gonski model provides an amount for each student plus extra for those who fall into six categories: Aboriginal, from low socio-economic areas, with a disability, from a small school, who speak English as a second language or are from a rural or remote school.
NSW Teachers' Federation Blacktown organiser Jason Gerke said 80 per cent of the Gonski funding was to flow in the fifth and sixth years of the initial agreement.
He said the Abbott government's pre-election stance that it would be irresponsible to make promises beyond a four-year budget cycle was weak.
"It's not a question of money, it's a question of political will and the priorities of the government," he said.
"There are massive investments in roads and infrastructure. Paid parental leave is something that they've obviously budgeted for beyond four years, so that argument is very weak."