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School leaders are calling for tighter limits on who qualifies for key worker status, after seeing an increase in demand from parents for their children to be given a place in the classroom.
Currently only one parent needs to be a key worker and one headteacher in Bristol has told ITV News he has a waiting list of children wanting to return.
Kevin Fry, co-head teacher at St Mary Redcliffe Primary School, said: "We can ask for evidence of their job role.
"If you're able to home school your child then please do so to keep the number in school as low as we possibly can, or alternatively to offer that place to a critical working family who desperately need that place so that they can perform their duty."
More than a quarter of the 421 pupils enrolled at St Mary Redcliffe Primary in the Windmill Hill area of Bristol are in school with staff having to prioritise whose case is most deserving.
But he said he said he recognises it is tough for many families to carry out home schooling, adding: "We're encouraging our families to do what they can, because it's really tough on a lot of our working families. So our advice is work with the maths, the reading, the writing, the core subjects."
Paul Whiteman, general secretary of school leaders’ union the NAHT, had heard of some schools with up to 70% of their families taking up onsite provision.
He said: “This could seriously undermine the impact of lockdown measures, and may even run the risk of extending school closures.”
According to the National Education Union (NEU), many headteachers have said that the increased number of key workers' children in schools "defeats the point of a move to remote learning."
Kevin Courtney, Joint General Secretary at NEU said: "The Government is not going to achieve its aim of 'reducing social contact across areas' if schools remain packed with students with the virus running rampant."