If it was me, I would try to coordinate a time for the master bedroom (eg wife and kids go to hang out at the cottage and come back to master finished). Move kids into one room. That frees up other kid room for renovation. Renovate one kid room, move kids to finished room and then do other kid room. You spend half your life relocating people/furniture but it can work. I ripped out carpet and put hardwood in our old house that way. Really sucked but couldn't come up with a better system as furniture had to be out of each room as it was done.
My wife's going to be away for a couple of weeks in January. Should I stock up on beer or sandpaper for the bedroom floor?