One of our favorite family
activies is Geocashing, it's a perfect 'treasure hunt' complement to sailing. Geocashes are spread all over the world (and very densely in the U.S.) and you find them by logging into Geocashing.com
and find a site near you. You plug
coordinates into your handheld GPS
and go off and find the cashe.
We have a couple handhelds aboard, so I can give one to each kid and have them make a race
out of it. We carry along a back-pack that contains some goodies to swap out when we find the cashe, a log book of the sites we found, spare water
bottles, backup batteries and some granola bars. Sometimes the hunts will take you on quite a hike.
In every case we've found cashes in cool places that we wouldn't have otherwise thought to venture, which has been the real treasure.
ps. i just did a quick search, there are 134 cashes in Norway!