England's children's commissioner is supporting the idea of using summer schools and longer school days to help pupils catch up on lost learning.
Anne Longfield warned that one in six children may never be able to catch up on school time that has been lost due to the pandemic without the right support.
Meanwhile, the government's new education recovery commissioner, Sir Kevan Collins, has said it could take years for schools to recover from the impact of the pandemic.
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Ms Longfield said: “There needs to be a boost for children in terms of catch up in education terms in the classroom, potentially as well using some of those times in school holidays (and) the longer day.
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“But part of that really needs to be as well about helping children to build back those social skills and that confidence.
“There’s a group of children who won’t make up the time they’ve lost. These are the ones who started behind, who are struggling.
“Potentially about one in six children if they don’t get that level of support and boost won’t ever catch up during their time at school.”
She told Sophy Ridge on Sky News that the catch-up measures needed to be in place, for children who have been struggling with learning at home, ahead of plans for schools to reopen next month.
The government is reportedly considering a number of options – including summer schools, extended school days and shorter summer holidays – as part of catch-up plans for pupils who have missed out on learning due to Covid-19.
Ms Longfield supported these proposals, saying: “Part of that really needs to be as well about helping children to build back those social skills and that confidence."
She said she hopes to see primary schools reopen sooner than secondary schools – with the government proposing a reopening date of 8 March – as trends across Europe show they can be managed in the pandemic.
Ms Longfield said: “Those children are less able to work at home remotely. Their parents need to be there because they need a greater level of care and support to learn.
“And they’re much less likely to pick up that level of infection or, indeed, potentially transmit.
“There are exam years as well that we need to look at for older children, but certainly for primaries, there seems to be a trend that actually smaller entities can be back open and can be managed.”
Meanwhile, Sir Kevan said it would take four or five years for schools to recover from the impact of the coronavirus pandemic.
He described the government’s commitment of £1.3 billion in funding to support the recovery as a “good start”, but added: “That isn’t going to do the job.”
On measures to help children catch up, he told Times Radio: “I’m completely open to everything being on the table and extending the learning time for children does need consideration and does need examination.
“We’ve got to be careful though. If you just increase the time without increasing the quality, the evidence is clear – that doesn’t deliver.
“You’ve got to increase the quality as well as the time.”