I have one of those wooden tiered book carts filled with board books so good for all and wheel that around the house as needed. We clean up small playroom upstairs - so not a lot of stuff while I cook lunch. I call them one at a time for diaper changes or potty as I start lunch and they clean. I have activities at the table such as puzzles if there is a gap between cleanup and lunch ready.

Then after lunch they sit near the bathroom door to read the books off the rack while I do diapers, potty, hands washed, etc. The babies are tucked into beds - upstairs in bedrooms as they are changed. Others return to books till all are done. Then we choose a book or two from the rack to read - nice thing is they are very short. Then into bed for the rest of them whichis mats in the mainfloor (diningroom) playroom they cleaned up before lunch. I set up the beds while they are eating.

Key for me is to have them moving as a group and doing the same things and putting babies into highchair or leaving them there a bit longer as a form of crowd control. I always do diapers before lunch so it is just a quick peak down the back and change only thost that need it. Once babies are out of the way and in bed I do potty for older ones. I get up in the reverse order so older ones are up and potty and reading or doing activities before I get babies up - it's like working with one group at a time instead of both at the same time.