The chief of an academy trust with schools in Norfolk has suggested they could consider a three-day week to offset the impact of rising energy costs and teacher pay rises.
Marc Jordan, chief executive of the Creative Education Trust, has revealed radical discussions as growing financial pressures leave academies searching for potential solutions.
The trust has four schools in Norfolk, all in the Great Yarmouth area, along with several in the Midlands.
He told the Telegraph he had "heard discussions about a three-day week" in an effort to cut costs.
He added that the trust is considering a recruitment freeze and could scrap Covid catch-up learning programmes and investments in school buildings.
He added: "Others less fortunate are facing significant deficits and are already planning for teacher redundancies."
The warnings come with energy bills forecast to soar to £5,000 per year for households, which would also mean significant increases in costs for schools.
It also comes after the government agreed to up its pay offer to teachers - which it is yet to provide funding for.
School leaders have warned that while the concept of a three-day week is highly unlikely, other measures were likely being considered as schools look to make up for the rising costs.
These include the possibility of building projects being scrapped or delayed, splitting responsibilities between existing teachers when senior staff members leave and employment freezes.
Lynsey Holzer, chief executive of the Evolution Academy Trust, which runs a dozen schools in Norfolk and Suffolk, said talk of a three-day week was "likely hot air" - but acknowledged the troubles facing trusts nationwide.
She said: "Like everywhere, the cost of energy rising is giving our organisations some significant headaches.
"We are all guessing about the percentage rising in line with all organisations but are also facing the prospect of significant financial pressure from the recent pay rise announcements from the government - which remain unfunded and come at the 11th hour.
"All my colleagues of course support rises for public sector pay, but this is putting additional strain on us financially.
"We are in constant talks in the organisation about how to mitigate these rising costs including adjustments to budgets and ways to make our energy use more efficient as part of a longer term strategy."
She added: "There has been no talk about a three-day week or anything in that line and I haven't heard that suggestion in wider forums. It would be very difficult to do both publicly and professionally."
Geoff Barton, general secretary of the Association of School and College Leaders, said: "We haven't heard directly from school leaders about any who are considering reducing to three or four day weeks.
"The range of options we have heard of include non-replacement of staff and leadership posts, with responsibilities redistributed across the remaining teams; putting on hold capital projects and the likelihood of increased class sizes in the future.
"Unfortunately, soaring energy costs and the staff pay for which there is no additional government funding means that school leaders are having to look at very significant cuts to their budget in order to avoid deficits and balance their books.
"This is extremely challenging as budgets are already very tight following a decade of real-time cuts in government funding.
"It is an utterly demoralising, depressing and desperate situation.
"The government has simply buried its head in the sand and is insisting that these costs are affordable - but at individual school level that is clearly not the case."
A spokesperson for the Department for Education said: “We recognise that schools – much like the wider economy – are facing increased costs, including on energy and staff pay.
“Our schools white paper set out our expectation that the school week should last a minimum of 32.5 hours – the current average – for all mainstream state-funded schools.
"Thousands of schools already deliver this length of week within existing budgets and we expect current funding plans to account for this.”
Efforts were made to contact Mr Jordan to elaborate on his comments.
Analysis by education correspondent David Hannant
Clearly these are extremely concerning times for those holding the purse strings of our region's schools.
The concept of a three or four-day school week seems highly unlikely and one that would come with a massive amount of complications - so to even think this is being considered speaks volumes.
Were it to become a reality it would be likely met with mass revolt from parents, who would face desperate scrambles to make alternative childcare arrangements.
For such an extreme to even be considered hammers home the severity of this situation though - and the need for the government to ensure the funding to back up its promises is delivered.
After the past two years of turmoil, which forced them to adapt extraordinarily, it is clear teachers are deserving of the increased pay offer being made.
But demonstrates that if it is not financially sustainable, it may be our children that are missing out - so the rise has to backed up with the funding to match it.
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