[Heel n Toe]

If you're gonna take time for a side trip to see Grand Canyon, try to also build in enough time to see Monument Valley... not too far... build in one extra day for it and stay at Goulding's Lodge. We were more wowed by Monument Valley than Grand Canyon... there's something about it that isn't easy to put into words.

It's eerie... I half expected to see a T-Rex. Or John Wayne.

Southeastern Utah: http://www.nationalparkreservations.com/monument_valley_map.htm

http://commons.wikimedia.org/wiki/Image:The_searchers_Ford_Trailer_screenshot.jpg
http://www.americansouthwest.net/utah/monument_valley/monument-pass-road2_l.html <---where Forrest decided to turn around and go home.
http://www.naturalimages.com/blog/uploaded_images/monument_valley_12-12-07_004-769246.jpg
http://upload.wikimedia.org/wikipedia/commons/6/6b/Monument_valley_panoramic.jpg

Meteor Crater (just east of Flagstaff) would probably be a major hit with your son, too.
http://www.wwu.edu/depts/skywise/gallery/snowder/crater.jpg
http://spacecenter.uark.edu/Meteor_crater_JD.jpg
http://slas.us/gallery/profiles/seano/Meteor%20Crater%20Arizona%201.jpg