Howard Fisher, the headteacher of a Church of England school in Kent, said he would rather have pupils restart an academic year than risk having to “lose a child”, he wrote to parents in a frank letter.
He has warned there “is no such thing as social distancing in a school” and saw “no solutions” yet for how they can reopen safely.
As part of the prime minister’s plan to ease the country out of the coronavirus lockdown, reception, year one and year six classes could be back in school by 1 June at the earliest, if safe to do so.
Johnson made his speech to the nation on Sunday outlining a step-by-step approach to get employees back to work and reduce restrictions on people and businesses.
Education secretary Gavin Williamson said the scientific advice indicates that more children can return to school.
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But Fisher, the headteacher of St George’s C of E Primary School in Sheerness, insisted that even by introducing precautions, the risk of the virus spreading will remain.
He said “sensible, rational” debate about “better solutions is missing”.
Fisher proposed returning to classes when there is “more science to support us”. Children of key workers are allowed to attend school but the government’s plan would represent many more returning.
“Believe me, I would rather any child repeats a year than go back too soon and have to lose a child; why is this not in the national debate; because it will cost money!” Fisher wrote.
In a brutally honest letter to parents, he said he was “not going to sit here and write to you to say we can achieve social distancing in a school”.
He went on: “We can always make things safer, we could perhaps reduce slightly the risk, but as soon as you open the school as far as my many years can tell you, the risk will be there.”
The headteacher of 15 years, who said he has taught since the nineties, said in the letter dated to Monday that “we have no plans sent from the government” but expected them to arrive during this week.
Government advice has said that class sizes should be limited to 15 pupils and staggered lunch and break times, as well as varied drop off and pick up times, should be implemented.
One way travel in school corridors should be considered, or a divider could be placed to help limit contact.
Primary pupils may also be sent to other schools, but families will not be penalised if they decide against taking up a place, the government has said.
“I can be truthful here and categorically tell you there is no such thing as social distancing in a school; it does not exist and would never exist,” Fisher wrote.
“The reason childhood illnesses spread in a school is surprise, surprise, we are all in contact with each other.
“I can put two children in opposite classrooms and they will still get chicken pox because that’s how it is in a school.”
He added that the school was left in a “quandary” and he had “heard no answers, I heard no solutions” and nothing he had been told put his mind at rest.
The Department for Education has been contacted by Yahoo News UK for comment.
Speaking to Yahoo News UK, Fisher envisioned children coming back in bubbles of about 10, which would not be able to interact with other groups.
He said that would be disappointing for the children when they come back and said reception and year one would be the “hardest” groups to explain social distancing too.
Fisher reiterated that “it is too soon” to reopen in July, in his opinion, and proposed September as a “much safer time” to bring back teaching in classrooms.
“You can start the children in a class with a teacher with a curriculum that you’ve actually got some sort of handle on,” he said, discussing opening in the autumn.
“Don’t forget these children have missed March all the way through to July.
“Getting a handle on that is going to be quite a hard task to do, and it isn’t a task we are going to achieve in the next six weeks.
“The next six weeks is around bubbles of children moving around school enjoying some form of schooling but it won’t be standardised lessons towards a goal or an aim.”
Gavin Williamson said: “The latest scientific advice indicates it will be safe for more children to return to school from 1 June, but we will continue to limit the overall numbers in school and introduce protective measures to prevent transmission.
“This marks the first step towards having all young people back where they belong – in nurseries, schools and colleges – but we will continue to be led by the scientific evidence and will only take further steps when the time is right.”
The joint general secretary of the National Education Union described the government’s plans as “reckless”.