Reach out for opportunities to help

Organizations that can help you help the worldEl Hogar. An orphanage and school for younger kids, plus agricultural and technical schools for older ones. El Hogar can't accommodate individual volunteers but will help you assemble a work team for a visit. 781-729-7600; elhogar.org

American Hiking Society. Trips, often in collaboration with other organizations, focus on trail construction and maintenance. 800-972-8608;

americanhiking.org

Catholic Volunteer Network. Short-term options include working with nuns in the Dominican Republic or encouraging sustainable farming practices in Appalachia. 800-543-5046; catholicvolunteernetwork.org

Earthwatch. Most expeditions focus on monitoring animal populations, from black rhinos in Kenya to songbirds in the Rockies, though the organization also offers several archaeological trips. 800-776-0188; earthwatch.org

Globe Aware. Some 4,500 volunteers a year join trips organized by this Dallas nonprofit; options include teaching English in Cambodia and planting trees in Romania. 877-588-4562; globeaware.org

Global Volunteers. An online clearinghouse of volunteer opportunities. Search by skill, region and date to find a trip that fits your interests and schedule. 800-487-1074;

globalvolunteers.org

Habitat for Humanity. Volunteers can sign up for construction projects in 36 countries and six states. 800-422-4828; habitat.org

Passport in Time. The U.S.

Forest Service's volunteer program. Travelers interested in the history of Native American nations will find an abundance of options focused on archaeology. 800-281-9176;

passportintime.com

Planeterra. Organizes 30 volunteer trips focused on community development in Africa, Asia and Latin America, combining tourism with volunteer activities. 416-260-0999; planeterra.org

Sierra Club. Clear debris from turtle nesting beaches in Puerto Rico, or remove nonnative species from the California seashore - two of some 300 "service" trips. 415-977-5500; sierraclub.org

Transitions Abroad. Start researching your trip on the country-by-country bulletin boards of this website, which lists volunteer opportunities around the globe with contact information for organizations in search of volunteers. transitionsabroad.com