Wigan borough schools are set to plummet down funding league tables if proposed changes go ahead, education leaders have said.
The warning comes as parents are being urged to back calls for the government to re-think a makeover of how schools are maintained.
Under the new formula, the borough will drop from 72nd to 109th in terms of funding across the UK, says the Wigan Schools Forum (WSF)
It follows on from numerous warnings from head teachers, union leaders and politicians in recent weeks about the impact of “unprecedented” budget cuts.
WSF chairman Adrian Hardy has written to parents asking for their support in calls for a re-think on the plans.
He says those calling for change should be encouraged by the recent government U-turn on controversial National Insurance Contribution plans.
And reports suggest Prime Minister Theresa May is considering tweaking the changes after a rebellion from Conservative MPs.
Mr Hardy told the Observer: “The Government says more money is being set aside in the schools budget than ever before but that’s because there’s more children in the system than ever before.
“To put it simply, they’re introducing a ‘fairer funding formula’ that’s not a fair system.”
The calls from the Wigan Schools forum follows a similar warning from the National Association of Head Teachers (NAHT) that parents will start to see tangible impacts of reduced funding imminently.
Wigan NAHT secretary Michael Wilson said earlier this year “the fight is on” for children’s futures with schools facing the prospect of cutting staff, fewer educational trips and delays in building repair works.
He said: “The reduction of the education service grant, introduction of apprenticeship levy and increases in national insurance and pension contributions mean that school budgets are already at breaking point.”
Education unions have also warned borough schools are facing a cut of £444 per pupil.
And in their parents’ letter, Wigan Schools Forum highlights each of the borough’s secondary schools will see their budget cut next year along with 88 out of 99 primary schools.
It reads: “Fundamentally there is insufficient funding within the education system nationally and locally to allow schools to meet the budgetary pressures they now face.
"The proposals represent a lost opportunity to introduce a funding formula based on the actual costs of educating a child, regardless of where they live rather than be based on historical spend and use of national averages.
“We would like your support in our attempts to get the government to change its mind and amend the planned new formula so it delivers what is set out to achieve and does not continue to treat areas such as Wigan unfairly.”
The consultation closes at 5pm this Wednesday although parents are also urged to write to their MP to voice their concerns.
The Department for Education has argued school funding will be more than £40bn in total for 2016/17, its highest level on record. But critics said these claims were misleading in that schools were now facing increased costs, meaning the settlement will mean a real-terms net loss.
The revamped National Funding Formula is due to come into effect from April 2018.
It is said to ensure fairer distribution between school authority areas. A Department for Education spokesman said: “We recognise that schools are facing cost pressures, which is why we will continue to provide advice and support to help them use their funding in cost-effective ways, including improving the way they buy goods and services, so they get the best possible value for their pupils.”
Following chancellor Philip Hammond opting not to unveil any funding changes as part of his Budget announcement, a rapidly growing rebellion among Tory back-benchers could be set to trigger a change.
“And the Prime Minister is said to be considering changes to avoid the embarrassment of a potential defeat in the House of Commons.
Mr Hardy said: “I think the Government will have to listen to the weight of public opinion and that’s why we’re asking parents to support the efforts to make the changes needed.
“If we look at what has happened with the U-turn on National Insurance contributions it shows what can be done.
“Our schools in Wigan are doing the very best to ensure pupils’ education are not adversely affected by what is going on but the longer this goes on obviously the more difficult this will be.”