All of the modelling of post-lockdown easing has very much recommended keeping the elderly and the vulnerable locked away still, and hopefully that will remain the case even as measures are eased. If no one the child comes into contact with, either at school or at home, is in that vulnerable group, then I would have thought the risks are relatively low, especially if measures are taken to mitigate the spread where possible.
In healthcare teams, there are risk assessments being done on staff, so BAME nurses are doing as much as they can virtually, but Caucasian staff are doing all of the normal work, albeit with protection equipment on. Again, you would hope the management at schools have been doing these kind of risk assessments on the faculty over the past few months.