Almost 2,000 Cornwall children were educated at home in the last academic year, figures show.
Data suggests the number of home-schooled children has increased since the coronavirus pandemic across England, although figures are incomplete.
Department for Education statistics show around 1,900 children were voluntarily taught at home in Cornwall in the 2022-23 summer term.
Across the country, around 97,600 children were home-schooled. Separate figures from the Office of the Schools Adjudicator suggest there were 60,500 in March 2019.
But it appears Covid is not behind the rise – the largest reason for children being withdrawn from schools was for philosophical reasons, of which 15,800 parents had chosen to do so.
Meanwhile, many parents chose to educate their children at home for their mental health – 12,200 across England, including approximately 220 in Cornwall.
Olly Parker, head of external affairs at children's charity Young Minds, said schools "can and should be supportive environments for young people".
However, he warned "anxiety, bullying, academic pressure, difficult relationships and a lack of support" can lead to some children avoiding school.
Mr Parker added: "Young people should be able to access support for their mental health when they need it, including in schools.
"Currently, mental health support in schools is a postcode lottery and the Government must commit to ensuring young people can access support in every school in the country."
The data also shows older children are more likely to be taught at home across England – in Cornwall, 67% were in secondary school, compared to 34% in primary.
Geoff Barton, general secretary of the Association of School and College Leaders, said home education is a "big undertaking" and parents should think very carefully before taking their child out of school.
He said schools have very robust policies on bullying and take the safeguarding of pupils extremely seriously, and encouraged parents to work through issues with schools.
He added while home school seems to have increased, we do not know the definitive figures as the Government has not introduced a register.