Cabazon Dinosaurs might have a few funny photo ops and the gift shop inside one of the dinosaurs had some cool stuff (15-17 years ago when I used to pass it).
The Thing--falls in the category of just plain weird. Admission is cheap. We used to pass this 4 times a year on the way to and from camps and always BEGGED to stop. I think it took 4 years of begging to get Dad to stop. NOT worth driving extra miles, but odd and quirky thing to stop at IF you are passing by. The number of billboards for it is amazing.
Outside of Tucson, AZ is the Arizona Sonoran Desert Museum ( http://www.desertmuseum.org/ ). It's a world renowned zoo specializing in animals of the region. If you go, plan on half a day at a bare minimum, preferably be there when they open in the morning as many desert animals take an afternoon nap to escape the heat.
I haven't been to Old Tucson, but it's a popular tourist attraction with great photo ops. http://www.oldtucson.com/
The Painted Desert (AZ)