This interactive data visualization includes three maps. The maps illustrate the increase and decrease in population density in the United States over three decades: 1920-1930, 1930-1940, and 1940-1950.  The legends on each map represent the change in population density for counties (people per square mile). Taken together, the three population density maps illustrate the changes in geographic mobility during the featured decades.

Geographic Mobility in the United States - 1920-1950

Students will examine maps to explore changes in population density in the United States during three decades: 1920–1930 (Post-Progressive Era), 1930–1940 (Great Depression), and 1940–1950 (World War II). They will then determine what happened during each decade that likely influenced geographic mobility.