Here's an interesting series of depression-era photographs. (Link)
Pictured above is Dorothea Lange's Migrant Mother (public domain). I remember this photo, in particular, from photography classes in J-school. The mother's face is famous. But what stands out to me, all these years later, is the kids hiding their faces. Are they just shy? Embarrassed by their situation? I know, as a kid, I was always fairly aware of how much our family did and didn't have. Did the mother not want their faces in the picture?
What ever the case, it makes the picture even more powerful.