Even school age kids home on PD or summer benefit from a being separate part of the day to regroup. When I had my own home plus any other school age back then the first hour of naptime was alone time meaning they chose something that they could do by themselves without interaction with another child or me in a place by themselves so curl up and read a book, colour, etc. That made it quiet for those needing to fall asleep and gave me an hour to clean up from lunch, eat my lunch and do what I needed to do without interruption. When all was done we would then do a "big kid" activity till the little ones got up - a privilege they could lose if I had to waste my hour to deal with them not being alone quietly.

There were a lot less issues in terms of behaviour if they had a break from each other.