Kids on moving day are stressed even when they don't show it. A few small things help a lot.
Plan their day
If possible, send them to a grandparent or friend for the actual move. If not, give the older ones a job (labelling boxes, walking the dog) and the younger ones a quiet corner with a tablet.
Pack their room last, unpack it first
On the other end, get their beds up and their toys out before anything else. Familiar things in a strange house help everyone sleep that first night.