As always, try to simplify.
Limit the amount of stuff the children may bring. Select a duffle bag of appropriate size for each. That is the limit. Do that for yourself too, if necessary.
Plan your meals, so that there is a minimum of groceries going back into the house.
Make sure the TT has its own set of gear: pots, pans, silverware, tools, flashlights, etc. Don't try to make the stuff you already have do double duty.
Be sure that all children who can walk and talk have their own jobs.
Treat it like an extension of you house. If it was a short trip and you are going again next weekend, just make the beds and leave the clean clothes in the drawers/closets. No need to strip it each time.
Our family of six lived in our TT for 30 days and 7000 miles in one trip once. My wife managed the TT like a submarine. No wasted provisions, no wasted space, everything in its place. Once you get a good routine, the children will just keep getting more and more helpful. Beware, when they are grown up, you will miss them when they don't go!