What Role Does Geography Play in the Census?

Objective

Students will be able to define and analyze different types of census geographic entities (such as census tracts, census block groups, and census blocks) and determine how data from these different geographic entities might be useful.

Materials

• Student version of "What Role Does Geography Play in the Census?" (8 pages, includes Item 1: Excerpt From Chapter 1 of the Geographic Areas Reference Manual; Item 2: Standard Hierarchy of Census Geographic Entities; Item 3: Examples of Census Tracts, Census Block Groups, and Census Blocks)
• Printed set of the terms and definitions (cut into individual slips ahead of time, one term or one definition per slip): Spatial, American Community Survey, Decennial Census, Boundary, Geographic Hierarchy, Geographic Entity, Administrative Entity, Legal Entity, Statistical Entity, Small-Area Data, Census Tract, Census Block, Census Block Group
• Tape or the board for posting matched term/definition pairs
• Pencils/paper for each student

Warm-up (~5 min)

1. Tell students they will be learning about how the U.S. Census Bureau uses geography to organize and collect data.
2. Have students read Item 1 (Excerpt From Chapter 1 of the Geographic Areas Reference Manual) — either aloud as a class, in small groups, or read it to them while they follow along.
3. Ask students: "What did you learn from this excerpt?" Take a few quick verbal responses to check basic understanding before moving on.

Main Activity (~25 min)

1. Term/Definition Matching (10 min): Hand out one slip (a term or a definition) to each student. If there are more students than slips, put students in small groups and give each group one slip. If there are fewer students than slips, remove a few matching term/definition pairs from the stack.
2. Have students walk around the room trying to find the classmate (or group) holding the matching term or definition.
3. Once a pair believes they have matched correctly, have them tape their term and definition next to each other on the board.
4. Review the board as a class. If any matches are incorrect, ask students to work together to identify and fix the errors, offering help as needed.
5. Use Item 2 (Standard Hierarchy of Census Geographic Entities) to explain how these geographic entities fit together in a hierarchy (for example, states are divided into counties, which are divided into smaller units).
6. Item 3 Review and Questions (15 min): Review Item 3 (Examples of Census Tracts, Census Block Groups, and Census Blocks) with the class, pointing out that scale can make the smallest areas (census blocks) look artificially large — remind students to check the scale in the key.
7. Have students work individually to answer the two questions that follow Item 3:
8. Question 1: How do census tracts, census block groups, and census blocks compare with one another spatially — which is largest, and which is smallest? (Correct order: census tracts are largest, census block groups are in the middle, census blocks are smallest.)
9. Question 2: How might data from these particular divisions be used, and by whom, based on what they learned in Item 1? Why is dividing geographic space this way useful?

Wrap-up / Exit Ticket (~10 min)

1. Have students share their answers to Question 2 with a partner.
2. As an exit ticket, ask each student to write a one-sentence response to this question: "What role does geography play in the census?" Students should try to find a common theme from their Question 2 discussion to help form this sentence.
3. Ask a few partner groups to share their Question 2 answers and/or their one-sentence responses with the whole class.
4. Collect the exit ticket sentences before students leave.

If Time Remains

If class time is left over, have students read the Census Bureau's blog post about census blocks (referenced in the student materials as an extension resource) and jot down one new fact they learned about census blocks to share with the class.