Resources for analyzing photographs as primary sources.
History Matters: Who Took the Photograph?.
Riis photography: http://xroads.virginia.edu/~MA01/davis/photography/home/home.html
National Archives: http://www.archives.gov/education/lessons/
Cultural Tensions: http://www.archives.gov/education/lessons/edison-petition/
Child Labor: http://www.archives.gov/education/lessons/hine-photos/#documents