Presidio Park Stewards 

Sometimes it seems like we have it so good around here. Even our volunteer work is relatively glamorous -- no working with corny religious charities for us! (Even our religious charities are cool, as in Glide Church.) Instead, we can hoof it out to the gorgeous reclaimed military installation and throw our shoulders into habitat restoration. This might include tearing out old invasive plants (usually in the summer months), or replanting native species (winter). If you're especially lucky, you might do the delicate, important job of seed collecting, which probably makes you feel like a rad scientist-Earth-goddess-glow-being. It's all organized by a coalition of park services and the Presidio Trust, who together have been running the former post since it demilitarized in 1994. Yep, we have it good around here. — By Hiya Swanhuyser

Website: http://www.natureinthecity.org

Price: free