Jason & Kelly - We took our kids to lots of National Parks in the 1990's, stamping our "Passport Books" at each one. We would buy the Golden Eagle annual pass that was available at the time, which got us some discounting (so much so that we referred to it as the "Golden Weasel").
You will have a lot of enjoyment in the path ahead. Our best advice is just two things: Carry an umbrella for shade during hikes on hot sunny days in the Southwest, and don't pressurize your camper plumblng by attaching the hose - fill your tank and just run the water pump instead.
Happy travels, may God Bless you, prosper you and keep you safe, always under His protection!