For example say I am usually timetabled to have a class of 30 for 1 hour each week.
Therefore under normal circumstances I'd teach 30 students for 2 hours each fortnight. In lessons there'd be some input from me, maybe a helpful video, some practise questions, group discussion, individual work, etc.
If I had 15 students for 1 hour a week with me and then 1 hour remote learning I'd move things round a bit. So when they were with me I'd want to check they were clear with the content and do some practise and maybe have a discussion. But the helpful video and individual work could be done whilst they are at home.
It would be a different way of thinking about lessons, but it could definitely be done. It would also be far less disruptive to learning than students in and out isolating all the time. It would allow social distancing in class and reduce numbers on buses and this would reduce the spread of all illnesses.