ubs may not open until April, nightclubs until June, but for millions of frazzled parents across England, Monday will be the most eagerly awaited landmark on the long road back to normal life, when schools reopen their doors to all pupils. However, for Boris Johnson it will be the start of an anxious few weeks as the government’s health experts monitor the impact of the “big bang” reopening on Covid infection rates. In an open letter in January, the prime minister declared himself “in awe” of parents juggling home schooling with jobs and household chores. That is why No 10 made a deliberate decision to put the return to school at the top of the list of priorities for reopening, amid intense pressure from Tory backbenchers concerned about the impact on children’s education and wellbeing, as well as parents’ ability to work. Johnson rejected calls from ministers including the education secretary, Gavin Williamson, to send pupils back after the February half-term and instead set the date of 8 March – three weeks after the top four priority groups had received their first vaccine dose. The speed and scale of the inoculations – more than 20 million people have had their first jab so far – has given ministers more political wriggle room than they might have hoped for. And during the extra fortnight of Zoom lessons around the kitchen table the number of new cases dropped further – there were 6,573 new case on Thursday, fewer than half the number two weeks ago. But some experts are still wary about the “big bang” reopening, and government insiders remain acutely conscious that the return to school will mean a big change in the number of social connections made by many households. “We feel like we’re definitely confident on going ahead: infections are now at a lower rate and we’ve vaccinated a lot more people – but of course we acknowledge that there’s likely to be some impact on cases: our challenge is to manage that,” said a No 10 source. At its 11 February meeting, the Scientific Advisory Group for Emergencies (Sage) reaffirmed its expectation that schools reopening would increase the reproduction number of the disease, known as R, by 10%-50% – not just because of children mixing, but parents meeting at the school gates. The Department for Education hopes that the regular testing of teachers, school support staff and secondary school pupils, as well as the availability of at-home kits for the parents of school-age children, will help to reduce the risk of large-scale outbreaks by identifying asymptomatic cases. The health secretary, Matt Hancock, is also more confident that with the virus less prevalent it will be easier to track and control fresh outbreaks, in a way that became all but impossible as the second wave took hold in the winter. “We have very, very detailed, quite granular levels of data – and because the prevalence is lower, there is less noise,” said a Department of Health and Social Care source. Labour has also backed the wider reopening. “We have always said that the best place for children to be is in schools: best for their learning and best for their social and emotional wellbeing,” said the shadow education secretary, Kate Green. But she said she would still like to see more support given to schools to make the changes necessary to create a Covid-safe environment, such as testing, spacing pupils out and improving ventilation. “Teachers and heads are still saying the government are not being forthcoming with help,” she said, reiterating Labour’s call for “Nightingale classrooms” to allow children to be taught safely without crowding. Unions representing teachers and other education staff issued a joint statement on Friday urging the government to review the impact of reopening over the Easter break. “The timing of the current reopening offers an opportunity to undertake a comprehensive analysis of the early data findings during the Easter holidays and to act on this decisively if there are any indications of a spike in infections in any part of the country,” they said. Johnson has promised to wait five weeks before proceeding to the next stage of his roadmap – four weeks to review the data, plus a week’s notice to announce any changes to the plan. The Conservative MP Robert Halfon, who chairs the education select committee, has been among the backbenchers pressing Johnson to open schools as soon as possible. “I’m very happy that the kids are going back,” he said. His main concern is that the testing regime is made to work properly – and that the thinking behind new guidance on mask-wearing in secondary schools is made clear to parents and students. “I think the mask policy has got to be clarified,” he said. “I think what parents want is an open letter from the chief medical officer, saying why he thinks masks are necessary in the classroom, and how long they’re going to be needed.” He warned of “mask anarchy” if the policy was not made clear. Williamson, widely tipped for the chop in a summer reshuffle, has been visiting schools this week highlighting the intensive preparations taking place, and the apparent enthusiasm of teachers to welcome their pupils back. If the return goes without a hitch, the political credit will be banked not by Williamson but by Johnson, already basking in the glow of the successful vaccine deployment, which helped him extend his lead over Labour to 13 points in a YouGov opinion poll this week. But every step in the roadmap is an epidemiological gamble – and this one is the riskiest of all.