Travelling with young kids made easy: Put an entire outfit (including undies and hair accessories) in a ziploc bag. One bag per day. When you get to the hotel, put the bags in a drawer and they can pick one per day. Huge time saver!
i've thought about making something like this to hang on the rear of the driver and passenger seats, that way the kids could have their own personal stash of in-car entertainment (magazines, colouring in books, travel games and small toys)