First, let me just apologize if this is old news to most of you, but I just ran across this information on the Dinosaur Train Geocaching Challenge, which began a couple years back. Since my children are grown now, I tend to be out of the loop on the latest PBS offerings for kids these days. My daughters were brought up on Barney, Arthur, and Blues Clues; which should give you an indication of how ancient I am.
Speaking of Dinosaurs, this themed challenge cache sounds like a great way to introduce your kids to geocaching, especially any kids that are fans of the show. Information on the site states, "The Jim Henson Company has enlisted the help of PBS stations, museums, zoos, and aquariums nationwide to hide Dinosaur Train themed geocaches." Each geocache features one of the dinosaurs found on the online Dinosaur Train Field Guide and contains educational information related to that dinosaur."
So any parents of young kids who are anxious to get their children out geocaching, I encourage you to use any means necessary to do so, as that window is only open for a very short period. Believe me, it's amazing how one day your kids love geocaching with you, and then suddenly the switched gets flipped and they think you are the biggest nerd and your hobby is totally lame. And there's no going back.