If you are in the San Francisco area with your family, a fun adventure awaiting you is the Presidio Habitats exhibition at the Presidio of San Francisco, a 1,491-acre National Historic Landmark and national park site. The FOR-SITE Foundation is partnering with the Presidio Trust to sponsor the exhibit through May 2011, Wed-Sun. See the Walking Map to find the eleven artworks scattered in the northwestern corner of the park. The pdf brochure can be downloaded here. The July 2010 Sunset Magazine had a nice article about it but I could not find it on-line. Here is another Sunset Magazine article about rediscovering the Presidio.