My own solution:
Schools should continue with remote learning (online learning/schoolwork packs).
The government should lift the restrictions on socializing with other households, and give holiday childcare clubs permission to open up, providing that they can keep kids spaced out at desks.
Parents who need to be able to work efficiently can then have their kids go to holiday childcare clubs, where the staff will put kids in rooms full of spaced-out desks, doing the same online learning/schoolwork packs as they were already doing at home. Not too many kids per room. They should use young staff who are low-risk in terms of coronavirus. If holiday childcare clubs need additional facilities in order to fit everyone in while allowing enough space, perhaps they could make use of unused venues like sports facilities or theaters? The government is going to have to bail out/support some industries. They may as well demand the use of these facilities for a bit, in exchange for financial help.
You will then have a mixture of, some kids doing online learning/schoolwork packs at home, some kids doing online learning/schoolwork packs in holiday childcare clubs, and some kids doing online learning/schoolwork packs in schools (the key worker kids who are there already).
The teachers will only have to plan one set of work for all the kids. Parents who cannot work properly in the current situation, will be able to work. The kids will get an education of some sort. No, it will not be perfect or brilliant, but these are difficult times, and I am buggered if I can think of any better solution.
The above solution will NOT stop the virus from spreading. It will slow its spread, however. That's the best we can hope for right now.