The children's commissioner for England believes some families are being "forced" to educate their children at home after a BBC investigation found the number making the switch has doubled in five years.
UK councils received more than 66,000 notifications of children being moved to home education in 2023-2024 - up from 28,000 in 2019-2020, figures from freedom of information (FOI) requests show.
Dame Rachel de Souza said she was "deeply concerned" by the figures, adding that home education was a last resort for children whose needs were not met by schools.
The government said it was reforming the special educational needs and disabilities (SEND) system so more children received earlier support.
It has also pledged to introduce registers for children not in school so local authorities can "better identify and support all home educated children".
Elective home education rose sharply during the pandemic and official figures will be released in December.
But ahead of that, figures obtained by the BBC through FOI requests reveal that:
at least 66,496 children moved to home education in 2023-2024. In 2019-20 the figure was 28,558
the North and Midlands saw the biggest percentage rises in England. At least 10,453 children moved to home education in 2019-20, compared to 27,502 in 2023-24
children moving to home education doubled in most regions, but more than tripled in the North East, and rose by 85% in the East of England