If you're entertaining kids in San Francisco, you've likely already hit the Zoo, the Academy of Sciences, and the Exploratorium. All those are great. But what if you want to show your children an adventure in the city's gorgeous and diverse outdoors, seek out the Urbia Adventure League. Founders Damien Raffa and Barbara Corff have dedicated themselves to getting S.F. kids outside and inspiring in them eco-literacy and sense of place. After learning about "questing," a tradition of creating and locating hidden boxes in the moors of England, Raffa and Corff worked with local experts to design and create fun outdoor treasure hunts, with an emphasis on the fun. They now have five booklets, road-tested by families, to guide your explorations of nature in the city. These include the enticingly named Seeking California in a World of Plants (Strybing Arboretum in Golden Gate Park), Islands in the Sky (the hills above the Sunset District), and A Hidden Creek Makes a Lake (Stern Grove). The booklets contain riddles offering clues for the children to find their way, both on the hunts and in their broader awareness of the natural environment around them. This is definitely about the journey, not the destination, but at the end of the treasure hunt, there should be a treasure, right? There is with Urbia, and it doesn't just come in a box.