Ofsted inspectors will meet with parents of children with special education needs who are not in school to assess how they are being supported.
Ofsted and the Care Quality Commission (CQC) will carry out a series of “thematic visits” to understand why children with special educational needs and disabilities (Send) are not in class.
It comes as the Government’s Children’s Wellbeing and Schools Bill is seeking to remove the automatic right for parents to home educate their children, if the young person is at risk of serious harm.
The proposed legislation includes registers in every local authority in England to identify children not in school, as well as giving councils power to intervene and require school attendance if the home environment is unsuitable.
The visits, which will take place between spring and summer this year, will look at the experiences of children with Send who are not registered at a school.
They will also consider the experiences of Send children who are on a school roll but are “flexi-schooled”, on a part-time timetable, or severely absent.
Last month, Ofsted’s chief inspector Sir Martyn Oliver warned of a rise of flexi-schooling – where parents home-educate their children for part of the week.
Guidance on the thematic reviews of children not in school, released by Ofsted and the CQC on Tuesday, said inspectors will meet “remotely” with parents who have agreed to participate.
Inspectors will also speak to children with Send to understand their experiences, but Ofsted said families can “opt out of meetings at any time”.
The visits will not result in judgments about individual local areas.
A report will be published in autumn, highlighting examples of good practice as well as identifying any “systemic concerns”, the education watchdog said.
Lee Owston, Ofsted’s national director for education, said: “We know from our inspections that the number of children with Send who are not in school has been growing to a concerning extent.
“It’s vital that the most vulnerable children are not out of sight and that they continue to receive the support they need, even when they are not at school.
“I hope these visits will help us to understand the experiences of these children, as well as the barriers local areas are facing in trying to deliver improvements for them.”
Margaret Mulholland, Send and inclusion specialist at the Association of School and College Leaders, said: “It’s right for there to be a focus on children with Send who are either not registered with a school or are not receiving a full-time education.
“These children will often have highly complex needs and it’s important that time is taken to understand how they can best be supported.
“There is currently an overlap between high rates of absence from school and special educational needs.
“Only by closely examining the reasons for this, and making a significant investment to put in place the support these pupils require, is this going to change.”