Image: Representation of U.S. population density

Image courtesy of the U.S. Census Bureau

Download this activity as a PDF.

One of the most common statistics used to describe a country is “density.” But what does this mean and is it really a good measure of population or any other characteristic of a place?

Assuming we are talking about population, density can be defined as the average number of people per square mile (or square kilometer). And this is the problem – it is an average that assumes people are evenly spread throughout the area being considered.

The population density of the United States is about 87 people per square mile (about 34 people per square kilometer), but reference to the 2000 Nighttime Map of the U.S. makes clear that the U.S. population is not evenly spread across the country. This map shows distribution, which can be defined as the actual arrangement or spread of people within a given area.

Testing the Definitions

a) Distribute the handout of population density by state (PDF). At the state level, the map shows a better picture of population distribution within the U.S., but there are still some obvious problems.


b) Have students locate your state. According to the handout, what is the population density in your state? Do the students think that the state’s population is evenly distributed throughout the state, as the map suggests?

c) View the U.S. Census Bureau’s "Gateway to Census 2000"

    i.    Use the drop-down menu under Data Highlights to select your state.  Click “Go,” then select the “State by County” table for “Population, Housing Units, Area, and Density.”

    ii.    Next, download a state/county outline map for your state

    iii.    Distribute maps and data and have students use the data in the column “Density per square mile of land area: Population” to construct a choropleth map of population density by county for your state.
    Note: A choropleth map uses decreasing shades of color to show decreasing numerical values. See the map on the handout for an example.

d.    Lead students in a discussion of density and distribution as they relate to the maps they have made. Is density a good measure of population?

Extending the Activity

Encourage students to discuss what factors may influence the distribution of population within your state.
Ask students if they think the population within your county is evenly distributed, as their maps suggest?  How can they test this?

Additional Resources

National Geographic EarthPulse

Celebrity Questions

Watch and see if you can answer the video questions from Keith Urban and astronaut Rick Mastracchio from the 2014 National Geographic Bee championship.



Answer More Questions

How to Help

  • Photo: Geo Bee Winners

    Fund a School

    Donations help fund schools to participate in the National Geographic Bee.

Winners' Video

  • geobee-2014-kids-990.jpg

    2014 State Winners

    Fifty-four of the nation’s brightest young geography whiz kids will gather in Washington, D.C., from May 19 to 21 to take part in the 26th annual National Geographic Bee.

Student Activities

Teachers can use these activities in the classroom to prepare students for the bee!

  • Photo: Map of the world showing areas of freshwater

    Geo-Scavenger Hunt

    Simply memorizing terms and place locations can be tedious and even boring. One solution is to make the task fun with an atlas-based scavenger game.

  • Photo: Map of languages

    Exploring Diffusion

    The movement of people, goods, or ideas from one place to another is a process known as diffusion, which plays an important role in shaping the characteristics of where we live.

  • Photo: Infared satellite image of hurricane Rita

    Tracking Violent Storms

    Springtime brings the possibility of extreme weather, including violent thunderstorms and tornadoes.

See More From the Study Corner »