Headteachers have called for a plan to prevent the emergence of new variants of Covid-19 further disrupting schools.
The Association of School and College Leaders warned that any increase in coronavirus cases could cause more problems for pupils who have already been affected by lockdowns in the past year as a result of the pandemic.
And it highlighted the fact that there are no plans to prioritise unvaccinated school staff or provide vaccines for pupils.
ASCL general secretary Geoff Barton said: "We are going to need a plan to minimise the potential for educational disruption caused by the emergence of new variants.
"Not only are there currently no plans to provide vaccines to pupils, or to prioritise vaccines for currently unvaccinated staff, but the existing Covid protocols mean that every positive case results in a wider group of close contacts having to self-isolate.
"The potential for ongoing educational disruption is obvious and this will need to be tackled in order to ensure that stability is maintained in the future."
His comments come amid concerns over a rising number of cases of the Indian variant in some areas of the country.
Schools in parts of the North West of England are being advised to continue with the requirement to wear masks in classrooms despite it being relaxed nationally.
Mr Barton was responding to new attendance figures, which show attendance in schools remained stable last week
He said: "We are pleased that pupil attendance has remained stable despite concerns about the spread of the Indian coronavirus variant.
"We cannot stress enough how difficult any disruption is at this time, with schools and colleges managing the assessment of students for GCSEs, A-levels and other qualifications following the cancellation of public exams.
"Any increase in coronavirus cases has the potential to cause further problems for students who have already been impacted by lockdowns over the past year and for the staff who are endeavouring to assess them."
The latest Department for Education (DfE) figures show that around 92 per cent of state school pupils were in class on May 12, similar to May 5.
Just under nine in 10 (89 per cent) of secondary school pupils attended, while primary school attendance was 95 per cent – both were the same as the previous week.
The DfE estimates that around one per cent of all pupils on roll – up to 85,000 children – did not attend school for Covid-19-related reasons on May 12, similar to May 5.