4:

4-H: Involving over 5.5 million youths, making it one of the largest youth organizations in the U.S.; it is a club for young people (5-19 years old) sponsored by the Cooperative Extension Service to foster agricultural, human environmental science, career development, citizenship, leadership, and other skills. Member youths are encouraged to acquire knowledge, develop life skills, form attitudes, and practice behavior that will enable them to become self-directed and productive members of society. The four Hs stand for Head, Heart, Hands, and Health.