ZIPLOCK BAGS for kids outfits!!!! It was so easy to dress kids and throw an extra outfit in your backpack "just in case". I have used this method since reading it here on EVERY trip short or long. What a time saver!!!
Also, Bring healthy snacks (bananas, apples or granola bars) and when your in line or the lines are to long and the kids get the munchies you can give them a healthy sanck.