Almost one in five pupils were in school last week, just days before wider reopenings, new attendance data shows.
The data also shows a large uptick in the proportion of staff on-site last week.
Forty-seven per cent of teachers and leaders were working on-site on March 4, up from 41 per cent on February 25. The proportion of teaching assistants and other staff also rose over the same period from 58 per cent to 61 per cent.
Pupil attendance reached 28 per cent in primary schools and 47 per cent in special schools last Thursday, up from 27 per cent and 44 per cent respectively the week before. Secondary attendance remained steady at 6 per cent.
Schools were closed to all but the most vulnerable pupils and the children of key workers from January 5 until last Friday.
Primary schools were expected to reopen to all pupils yesterday, while secondary schools are allowed to phase the return of pupils this week to facilitate testing on-site.
Attendance has been rising since January
Despite partial closures, attendance has risen gradually this term, from 13.4 per cent in all state-funded schools on January 11 to 18.7 per cent on March 4.
Attendance in primary schools last week was seven times higher than the average for the lockdown last spring, and six times higher in secondaries.
The rise has been driven by an increase in the number of vulnerable and key worker children attending.
On March 4, around 1,013,000 key worker children were in attendance, up from 1,000,000 on February 25 and 820,000 in early January.
Last week, 47 per cent of all pupils with an education, health and care plan attended school, up from 45 per cent on February 25 and 34 per cent on January 13.
The proportion of children with a social worker attending school also increased from 40 per cent on January 13 to 50 per cent on February 25 and then again to 51 per cent last week.