Compeer
Nationwide network of volunteers who befriend children and adults suffering from a mental illness. Gives details of local chapter.
http://www.compeer.org/
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National PTA
Learn more about the history, services, and initiatives of this national volunteer organization, who work on behalf of children and youth.
http://www.pta.org/
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Peace Corps
US government supported volunteer organization with participants involved in projects in more than 80 countries.