Habitat for Humanity
This well-known organization builds and finances modest homes for families in need. Funded entirely through donations, the homes are built by volunteers dedicated to giving families a warm, decent place to live. The group offers kids older than 16 the opportunity to help out at construction sites by allowing them to take part in all types of building responsibilities. Although younger kids can't wield an actual hammer, children as young as 5 can participate in the cause as press agents, fundraisers and other youth roles that are heavily promoted by the organization.