This is fun! We went back out after dinner and found 1 cache (super small, just enough for a log, which we signed), and then got the first three spots in a four-part cache. The woods were super mosquitoey and the GPS couldn't get a signal so we are postponing the last part until a sunnier time. Also, though it's probably cheating, now that we have the coordinates for the cache, we can map it.
The first set of coordinates led Jim to hot glue in the cap of a fence post, which had been molded around a film canister holding the second set of coordinates - very clever. Then those led to a small black box magneted to the bottom of the fishing dock; after Jim narrowed down the location, Aidan found the box! The third set of coordinates led to a lamppost on the other side of the park - I figured out that the bolt covers at the bases of the lamps could be lifted, and underneath Aidan found a film canister with the last set of coordinates. We wandered around in the woods for a while and temporarily gave up when the mosquitoes picked up Esme and we had to all hang onto her legs to keep her from flying away with them!
This is really fun! Cheap entertainment for the whole family, and exercise into the bargain. The kids bring along their binoculars and walkie-talkies (hardly necessary, but fun), Jim drives the GPS and I carry the printouts. We probably walked about two miles tonight, just looking for stuff. You have to try this!