This is what the dfe asked MNHQ to publish on a recent thread (although unfortunately, the request got delayed and was only put on the thread concerned about a dozen or so posts before the 1000 mark, so it sadly didn't get the traffic intended).
"We are aware of some media reports last week regarding the transmission of Covid in schools and understand this has the potential to raise some concern."
"Last week, SAGE (the Scientific Advisory Group for Emergencies) published papers relating to the latest evidence of incidence and transmission of coronavirus in schools."
"The science is clear that children and young people are typically at very low risk from Covid-19 The disease is much less severe for children, even if they do catch coronavirus. And staff are not at higher risk than those working in other sectors."
"Furthermore, the papers say there is no clear or conclusive evidence that schools are playing a causal role in transmission and the spread of Covid-19."
“This is probably because education settings are rigorously enforcing all the mitigations – handwashing, mask wearing, bubbles, isolation of staff and pupils with symptoms etc.”
"The latest weekly figures show that 99% of schools are open and that only 0.2% of pupils are isolating at home with a confirmed Covid-19 case."
"As a department, we have ensured that all schools continue to operate with strict safety measures in place to minimise the risk of infection."
"You can read more about transmission in schools here."