Ms Spielman said the impact of Covid has not “aligned neatly with patterns of vulnerability or deprivation” and even many of the highest achieving children had “struggled with motivation” away from school.

“Almost all children felt the impact of Covid-19 and the resulting restrictions to some extent,” she said. “Many of the youngest children had their development and progress hampered, with some even regressing. Given the vital importance to children of a good start in life and the learning potential of the youngest children, this must not be overlooked.

“The impact of Covid has not aligned neatly with patterns of vulnerability or deprivation. Nearly all children have been affected to some degree. Even many of the highest achievers struggled with motivation away from the discipline and structure of school. 

“And even the best teachers found it hard to translate classroom instruction and inspiration into lessons with the same impact at the kitchen table.”

Her comments came after Department for Education figures showed that the number of children and staff off school for Covid-related reasons in England has risen in recent weeks. Education unions have warned that disruption to schooling is likely to worsen following the emergence of the omicron virus variant.

In Ofsted’s annual report, Ms Spielman said the message around the harm that lockdowns cause children – and the importance of in-person schooling – “needs repeating now”.

“Although many children are necessarily out of school because of Covid or other illness, it is important that they attend every day that they possibly can,” she added.

The watchdog’s report assesses education and children’s social care over the 2020-21 academic year. During this period, much of Ofsted’s routine inspection work was suspended but inspectors went on monitoring visits to see how schools, colleges, nurseries and social care providers responded to the pandemic.

Ofsted found that, despite the best efforts of many thousands of parents, teachers, social workers and carers, the challenges of the pandemic were so great that nearly all children fell behind in their education.

The report said: “In primary and secondary schools, children struggled with a hokey-cokey education – in the classroom, at home, separated in bubbles, isolating alone. Further education students and apprentices saw their classroom doors closed, their placements curtailed and their job prospects limited.”