The local Girl Scouts branch is a force; nearly 30,000 Bay Area girls are registered, with over 19,000 adult volunteers. Their credo is "Where girls grow strong," and selling Girl Scout cookies is only a small part of getting there. On field trips and through mentorships with local employers, the girls learn about science, business, arts, and themselves. The organization also hosts spring and summer camps. Joining is easy. Call the central number to register; you'll be assigned to a troop in your neighborhood. Each troop meets as often as the parents want them to and frequency can range from one to four times a month. Girls in first through fifth grade are eligible for Brownies; from sixth through twelfth grade they join the Girl Scouts.