Education secretary Nadhim Zahawi has called on ex-teachers to sign up from today to help with Covid-19 staff shortages in the new year.
Former teachers who are available to return to the classroom should apply on the Get Into Teaching website, he said.
They should ideally start the process before Christmas Eve to be ready to join the workforce from January, he added.
The plea comes amid reports that some schools have experienced very low attendance among teachers and pupils ahead of the Christmas break.
The highly-transmissible Omicron variant is expected to cause even higher staff absence levels in the spring term, and headteachers’ unions have warned of possible disruption to in-person lessons.
School leaders and academy chain chiefs are preparing for the possibility of having to switch to online learning next term - and some pupils have been asked to take laptops home before Christmas just in case.
The government is pleading with recently retired teachers, or those who trained as teachers and changed careers, to “find even a day a week for the spring term to help protect face-to-face education”.
Russell Hobby, CEO of Teach First, has also suggested that its alumni who have left teaching may be able to help schools to stay open.
Yesterday Tes revealed that Labour’s shadow schools minister Stephen Morgan had written to ministers urging them to develop a proper workforce plan to ensure schools stay open in the new year.
Mr Zahawi said: “It has been my absolute priority since day one in the role to do everything in my power to protect education - which is why today I am asking any teachers no longer in the profession to come forward if they are available to temporarily fill absences in the new year.
Although 99.9 per cent of schools had consistently been open this term, further action was needed as cases of Omicron increase, he said.
Mr Zahawi added: “Anyone who thinks they can help should get the process started now on the Get Into Teaching website, and everyone should get boosted now to help reduce the amount of disruption from the virus in the new year.”
From Monday, those eligible to apply can expect to receive targeted communications encouraging them to participate.
The Department for Education says it wants to help schools, unions and supply teacher agencies to reach potential teachers through social media and other communication channels.
The DfE said former teachers should approach supply teacher agencies listed on the website, as they will manage local supply.
The government is also working with the teacher training programme provider Teach First, whose CEO, Russell Hobby, said: “Given the challenges that schools now face, we want to see what more can be done to help - including how we, and those of our alumni who have trained as teachers but currently work outside the profession, may be able to support schools to remain open safely in the new year.”
Education unions and Labour have warned that the government’s actions are unlikely to be enough to solve the staff shortages problem, saying they came too late in the day for an already critical situation.
Paul Whiteman, general secretary of the NAHT school leaders’ union, said: “Having a greater number of supply teachers to call upon could be helpful, but it will not take away from the very challenging circumstances schools find themselves operating under.
“We need to be very clear that if things get to this stage, it will mean that education will look very different in January and we could be talking about a very different type of provision at the start of next year. That has huge implications for things like exams, assessment and inspection.”
Stephen Morgan, shadow schools minister, said: “This is a sticking plaster and only part of what’s needed to keep children and staff safely in class next term.
“The government’s failure to get a proper workforce plan in place leaves staff, children and parents relying on goodwill from retired staff and volunteers, many of whom face additional risks themselves.”
