Parents have been urged to keep children at home unless there is “no safe alternative” after the government published an “extensive” list of key workers who can still access schools.
The guidance, published early on Friday, has left teachers confused about how they will be able to operate amid staff shortages when the number of pupils admitted could be high.
Schools will be unable to cope with the demand if all parents deemed as essential workers in the fight against coronavirus send their children to school on Monday, headteachers have warned.
Geoff Barton, general secretary of the Association of School and College Leaders, said heads were “surprised” by the extent of the list as schools are already operating on very reduced staffing.
Mary Bousted, joint general secretary of the National Education Union, warned that the government’s “very long list” could result in some schools having the “majority of pupils attending”.
Frontline health and social care staff, people involved in food production and delivery, and utility workers are among the occupations of parents whose children can be cared for at school amid the coronavirus.
Doctors, nurses, police, journalists and teachers are also on the list, along with “administrative occupations” key to the effective delivery of the coronavirus response in local and national government.
Staff needed for “essential financial services provision”, such as bank workers, key telecommunications staff and postal services and delivery workers, are also included.
Children with at least one parent or carer identified as critical workers by the government could send their children to school if required, according to the Department for Education (DfE) guidance.
“If everybody who is potentially covered by the list sent their children to school on Monday the numbers would be significant, and schools would be overwhelmed, particularly small schools,” Mr Barton said.
He added: “We are advising that these parents should only send their children to school if there is no safe alternative. We are advising our members that it is their decision which parents they offer this option.
“If they receive additional requests then it is their call on whether or not to accept that request.”
Paul Whiteman, general secretary of the National Association of Head Teachers, said taking up a place at school should be a “last resort” for the minority of key workers who have no alternative.
The DfE said it expected the majority of schools to stay open to vulnerable children and children of key workers next week where required, but it recognised it may be “impossible” for small rural schools.
It said when a school is unable to stay open, it would work with local officials to find an alternative setting for pupils and it would provide transport arrangements.
But Mr Whiteman added: “School leaders have many questions that remain unanswered about how this will work in practice.”
A Downing Street spokesperson said on Friday it could not say how many children were expected to turn up at school next week.
