GEOGRAPHIC MOBILITY IN THE UNITED STATES — 1920–1950

TEACHER VERSION

Subject: High School History
Grade Level: 9–10
Time Required: 45–60 minutes

Learning Objectives

• Students will analyze, compare, and interpret maps of U.S. population density from three periods in the early 20th century.
• Students will understand how events during these three periods affected geographic mobility (the ability of people to move from one place to another).
• Students will understand more recent trends in population movement.

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Activity Description

Students will study maps showing changes in population density—the number of people living in a given area—across three decades: 1920–1930 (the years just after the Progressive Era, a period of social and political reform), 1930–1940 (the Great Depression, a severe economic downturn), and 1940–1950 (World War II). For each decade, students will figure out what historical events likely shaped where people moved. They'll then look at more recent data, from 2000–2010, to spot patterns in how Americans have continued to relocate.

Topics: Data visualizations, geographic mobility, the Great Depression, migration, population density, the post-Progressive Era, World War II

Skills: Analyzing change over time, comparing and contrasting, making predictions, reading and interpreting maps

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Materials Required

• The student version of this activity (3 pages)
• A computer with internet access for each student
• Optional: a teacher computer and projector to display websites

Online Tools Used

• Before and After 1940: Change in Population Density — census.gov/dataviz/visualizations/010
• Population Change by Decade, 1910–2010 — census.gov/dataviz/visualizations/049

For background on the Census Bureau, see "Census Bureau 101 for Students," which can be printed for class use.

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Standards Addressed

This activity supports the Common Core State Standards for reading in history and social studies (specifically, the skill of combining data—like charts and maps—with written analysis), the UCLA National History Standards on the Great Depression, World War II, and postwar America, and Bloom's Taxonomy, since students must analyze how historical events shaped population movement.

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Teacher Notes

Before the Activity
Students should understand two key terms:

• Geographic mobility — the ability of people to move from one place to another
• Population density — the number of people per unit of area

They should also have basic background knowledge of the economic, political, and social changes that took place during the post-Progressive Era, the Great Depression, and World War II.

During the Activity
Teachers should circulate and check on student progress.

After the Activity
Teachers should choose (or have students choose) a text in which the author argues that some specific factor is influencing—or will influence—U.S. population change. One option is the 2016 NPR article "Do Americans Really Move To Canada Because Of Politics?" Teachers can then ask:

• What does the author say or predict about population change, and what might this mean for the country's future?
• What factors, including historical events, does the text say affect population change today or in the future?
• Do you agree with the author's argument? Support your view using this activity, comparing the population changes described in the text with those from the post-Progressive Era, the Great Depression, or World War II.

As a wrap-up discussion, ask students:

• What did you learn?
• What are you still curious about?
• What was the point of this activity, and why does this information matter?

Extension Idea
Have students read an excerpt from, or watch a clip of, The Grapes of Wrath, which portrays geographic mobility during the Great Depression.

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Student Activity

Learning Objectives

• I will analyze, compare, and interpret maps of U.S. population density from three periods in the early 20th century.
• I will understand how events during these periods affected geographic mobility.
• I will understand more recent trends in population movement.

1. Open the Before and After 1940: Change in Population Density tool. It shows shifts in population density at the county level in 10-year intervals. Look at the 1920–1930 map and describe, in your own words, the trends you see.

Sample answer: Counties in northeastern states saw some of the largest increases in population density.

2. Which regions saw population density decline, and which saw little change?

Sample answer: Some southern regions, such as areas near Georgia, and parts of the East Coast saw declines. The northwestern United States saw little movement.

Note for teachers: During this decade, population density mostly declined in rural areas, reflecting a broader shift of people moving into cities.

3. How might increased industrialization—the growth of factory-based industry—during this period help explain these changes?

As farming became more mechanized, many former agricultural workers, including large numbers of African Americans, moved from the South to the North and West seeking jobs. These workers also moved to take advantage of growing industrial cities in the North.

4. Now look at the 1930–1940 map. Describe the trends in your own words. How do they differ from the 1920–1930 period?

Sample answer: The pattern changed—declines now occurred in the Great Plains rather than in the South and East.

5. How might agricultural and economic events explain the population changes between 1930 and 1940?

Sample answer: The Dust Bowl, a severe drought and set of dust storms, forced people to leave areas stretching from Texas through the Great Plains and move to places like California and larger cities. An infestation of boll weevils (crop-destroying insects) also bankrupted many farmers and sharecroppers, pushing them toward cities for work. Meanwhile, New Deal programs—federal efforts to boost the economy, such as building the Hoover Dam and creating the Civilian Conservation Corps—drew people to areas with available jobs.

6. Now look at the 1940–1950 map. Describe the trends and explain how they differ from the other two decades.

Sample answer: This decade shows more geographic mobility than the other two. Many counties in the Northeast, Midwest, and along the West Coast gained population density, likely because people left rural counties for more urban, populous ones.

7. How did mobilization for World War II—the process of organizing people and resources for the war effort—affect population shifts between 1940 and 1950?

Sample answer: People relocated to work in centers producing war supplies. Women, in particular, moved to take jobs that had been held by men who were now fighting overseas.

8. Based on all three decades, what were the major push factors (forces driving people away from an area) and pull factors (forces drawing people toward an area) shaping population density in the early 20th century?

Sample answer: Major push factors included agricultural depression and increased farm mechanization. Major pull factors included war mobilization and industrial growth.

9. Open the Population Change by Decade, 1910–2010 tool and click play to watch population shifts over time. What trends do you notice from 2000–2010?

Sample answer: The U.S. population shifted toward the West and South.

10. Based on the overall trends in this data, what population changes do you predict for five years from now?

Answers will vary.