The Camp Meeting and Benevolent Societies
http://lcweb.loc.gov/exhibits/religion/rel07.html
Generously illustrated with artifacts and documents from the Library of Congress, these concise sections are very accessible to secondary level students.  Part of the Library's outstanding online exhibition Religion and the Founding of the American Republic.

Revivalism and Benevolence
http://www.wfu.edu:/~matthetl/perspectives/seven.html
Highly readable lecture from Dr. Terry Matthews for his course "Religious Life in the United States" at Wake Forest University (NC).

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