The “alarming” level of children missing school has become a “stubborn and damaging issue”, according to the chief inspector of Ofsted, England’s schools regulator.
Sir Martyn Oliver said he was also worried about a rise in “flexi-schooling”, where parents educate their children at home for part of the week.
It is not clear how many children are taught in this manner.
The Department for Education (DfE) said the government was putting education “back at the forefront of national life”.
Ofsted’s annual report said attendance issues had “deepened” since the pandemic.
Around 158,000 children missed at least half of their classes in the autumn and spring terms of the last academic year, it said, citing the latest DfE figures.
In Knowsley, more than a quarter of pupils were classed as persistently absent – meaning they missed 10% of the school calendar, or more.
Blackpool, Bradford, Middlesbrough, Sunderland, Bristol, Torbay and Plymouth followed Knowsley with the next highest rates of persistent absence – with between 23% and 25% of pupils missing significant periods of school.
Ofsted’s report also said education had “become fractured and fragmented for too many children”.
It found “a small number of schools” allowed children to be flexi-schooled. However, because this is often recorded as an authorised absence, it is not clear how many pupils are in this situation.
The report said that a “hybrid form of education”, where children learn through a mix of online and in-person lessons, was “increasingly used” for children with Special Educational Needs and Disabilities (Send), or those with behaviour or health needs.
Around 34,000 children are thought to be educated according to part-time timetables, and 92,000 are estimated to be home-educated.
The report said many home-educated children received a good education, but they were still part of a significant number who have “been opted out of more orthodox patterns of education”.
Julian Frances, a parent from north London, told the BBC his Year 8 child had autism and ADHD and struggled to attend school, even on a reduced timetable.
April – who uses they/them pronouns – has not fully attended school since the pandemic. The 12 year old has found it challenging to learn in classrooms with other students since lockdown measures were lifted – especially when there is lots of noise.
“The other week, I had to go and pick them up and they were in complete distress,” said Mr Frances. “They couldn’t talk to me for 20 minutes until they had calmed down.”
“They can’t even express how it feels – it’s just this complete overwhelming sense that they can’t deal with everything.”
Mr Frances and his wife work full-time, so, although they help April with homework, the couple cannot be at home all the time to provide for home-schooling.
April is a keen reader and recently finished The Great Gatsby – but Mr Frances is concerned that it’s not on the syllabus.
“If you talked to them, you’d say they had great general knowledge [and] they’re a well-educated child.
“But the fact is they’re not going get any qualifications because they’re not on the pathway.”
The BBC has contacted Frederick Bremer School for comment.
Education Secretary Bridget Phillipson recently announced £740m to increase the number of places for pupils with Send in mainstream schools.
Asked about the government approach to Send on BBC Radio 5 Live, she said: “We just need to look afresh at the system as it stands. Parents have lost confidence, the outcomes for children are not good, and sadly we are spending ever rising amounts.”
Sir Martyn said part-time schooling could be an effective temporary measure to help get children back into school, but this hybrid style of education was “not an excuse to avoid full-time schooling throughout school years”.
Ofsted added it made it more difficult for children to receive a coherent education.
In a briefing with journalists, Sir Martyn accepted that the shift to parents working from home since the pandemic had not helped attendance – particularly on Fridays, an issue which was flagged by England’s children’s commissioner last year.
Ofsted also warned a shortage of skilled staff, from early years onwards, remained a challenge, as new figures show that teacher recruitment targets in England have been missed for a fourth consecutive year.
Concluding Ofsted’s annual report, which focused on a broad range of issues including attendance, Sir Martyn said: “There are no silver bullets (and there will never be enough silver to go around), but many of the problems can be mitigated through joined-up thinking and partnership working.”
A DfE spokeswoman said: “As the report highlights, education is fundamental to the future success of this country – that’s why we are putting it back at the forefront of national life once again.”
She added the government was working with Ofsted to introduce school report cards, which would “give parents a more complete picture of school performance” and help improve standards.
Meanwhile, a report from Sport England suggests that the pandemic has had “a fundamental impact” on exercise habits among children.
It found the percentage of Year 7 pupils who could swim 25 metres without any help stood at 70% in the most recent data, down from 77% six years ago.
Girls are less likely to be active than boys, it suggests, as well as black and Asian children and those from the least affluent backgrounds.
Tim Hollingsworth, Sport England’s chief executive, said: “The data shows that, for the children whose impressionable early years were defined by lockdowns and lack of activities, attitudes towards sport and physical activity are distinctly negative.”
Additional reporting by Hayley Clarke.