Photogrammer is a fantastic geography and history website. Yale University put together this collection of 170,000 pictures takes from between 1934-1945. These images are organized on maps, making the world interactive and engaging.
These images can be searched by state, county, photographer, categories, and even year taken. The search option provides powerful ways to get exactly what you like out of this collection. For example, I searched for the word homeless and came up with 20 images. These were from all over the nation.