This museum is so worth the drive. If you want to head south from Vegas, stop at Ethel M, go to this museum, and then head to the Hoover Dam - there I planned a whole day in Vegas for you!
At $1.50 per adult, and $1 per kid, this museum is way underpriced. It has a nice indoor collection and the outdoor area that is very interesting and gets you moving after the short drive. We spent about 90 mins here checking out all of the exhibits and I highly recommend it to locals and travelers.