Students learn about population density within environments and ecosystems. They determine the density of a population and think about why population density and distribution information is useful to engineers for city planning and design as well as for resource allocation.
Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.
All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standard Network (ASN), a project of JES & Co. (www.jesandco.org).
In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.
Click on the standard groupings to explore this hierarchy as it applies to this document.
- Colorado: Math
- Colorado: Science
- Common Core State Standards for Mathematics: Math
- 2. Multiply or divide to solve word problems involving multiplicative comparison, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem, distinguishing multiplicative comparison from additive comparison. (Grade 4)  ...show
- 3. Apply the area and perimeter formulas for rectangles in real world and mathematical problems. For example, find the width of a rectangular room given the area of the flooring and the length, by viewing the area formula as a multiplication equation with an unknown factor. (Grade 4)  ...show
- 2. Represent real world and mathematical problems by graphing points in the first quadrant of the coordinate plane, and interpret coordinate values of points in the context of the situation. (Grade 5)  ...show
- International Technology and Engineering Educators Association: Technology
- C. Individual, family, community, and economic concerns may expand or limit the development of technologies. (Grades 3 - 5)  ...show
- Next Generation Science Standards: Science
- Define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost. (Grades 3 - 5)  ...show
- Describe the biosphere and discuss its components.
- Describe how population and population density affect an organism.
- Identify how engineers apply knowledge of population density to the development of space, such as land and building capacity.
Each group needs:
- Meter stick (share among teams if supply is limited)
- Population Density Worksheet
|Nonliving, for example, sunlight or rocks.|
|A human-made, closed environment containing plants and animals existing in equilibrium.|
|The part of the Earth's atmosphere that is capable of supporting life and includes both living and nonliving things.|
|Pertaining to life or living organisms.|
|A functional unit consisting of all the living organisms (plants, animals and microbes) in a given area, and all the nonliving physical and chemical factors of their environment, linked together through nutrient cycling and energy flow. An ecosystem can be of any size — a log, pond, field, forest or the Earth's biosphere — but it always functions as a whole unit.|
|A person who applies scientific and mathematical principles to creative and practical ends such as the design, manufacture and operation of efficient and economical structures, machines, processes and systems.|
|The surroundings in which an organism lives, including air, water, land, natural resources, flora, fauna, humans and their interrelationships. (Examples: Tundra, coniferous forest, deciduous forest, grassland prairie, mountains and rain forest.)|
|The natural home of a plant or animal.|
|The number of persons inhabiting a country, city or any district or area. (ecology) The number of a specific type of organism living in a particular environment.|
|Population per unit of land area; for example, persons per square kilometer of arable land.|
Before the Activity
- Gather materials and make copies of the Population Density Worksheet, one per pair of students.
- Take a moment to show students photographs or graphs that illustrate the world's population. See Figure 1 and Figure 2, or look at the U.S. Bureau of Census website at http://www.census.gov/ipc/www/world.html.
With the Students
- Divide the class into teams of two students each. Assign one student to be the measurer (with the meter stick) and the other to be the recorder (using the worksheet). Tell the students that they are acting as engineers who need to know the population density of the classroom in order to help design safety evacuation procedures.
- Have the students make the following measurements and record them on their worksheets:
- Use a meter stick to measure the length and width of the classroom.
- Multiply the length and width to get the area of the classroom in square meters.
- Count the number of individual people in your classroom (remember to count the teacher[s]).
- Calculate how much space each person has by dividing the number of square meters in the classroom by the number of people.
- Predict the amount of space each person would have if your class size doubled. (For example: If the student population is 20 and the classroom size is 200 square meters, then each student would have 10 square meters of space. Repeat the above calculation. If the population density of the example classroom doubled, each person would have only 5 square meters of space.)
- Calculate the population density of the class by dividing the number of people in the classroom by the area to get individuals per unit area. (In our example, the population density is: 20 students/200 square meters = 2 students per 20 square meters = 1/10 = 0.1 students/square meter.)
- Have students practice more population density problems by completing the worksheet table.
- Conclude with a class discussion to review the worksheet and discuss population density trends. How does the population density of the classroom affect the amount of resources (tape, paper, chairs, space, etc.) for each student? (Answer: The amount of resources decreases with an increase in population density.) How might an engineer use the population density of the classroom to design a good safety evacuation procedure for the class in case of a fire drill? (Answer: Engineers would use the information to find the safest number of students to have in the classroom and the best way to get them from the classroom to outside the building quickly.) How many exit doors are there in your classroom? How many exit doors are in your school's auditorium, cafeteria or gymnasium? Why are they different? Tell the students that they will use the knowledge of population density to figure out how organisms and environments interact inside our biodomes.
- How does the number (amount) of individuals in a group affect each individual organism? (For example, how does sharing a classroom with other students affect each of them?)
- In your science classroom, how much space do you think each person has?
Activity Embedded Assessment
- Have students list the groups of living things that might be in the environment near where they live.
- Show students a graph of the world's population growth over time (actual and projected) to illustrate how population size changes (see Figure 2).
- Write Table 1 on the board. Have students study the data and hypothesize what may have happened to change the population density. (Possible answers: Animal population grew with abundant food, water, shelter and protection from dangers [people, cars, predator animals]. Animals died off if there became too many of them for the limited amount of food, water or shelter. Animals died if they became too crowded and moved closer to dangerous human activity [cars, people, new development of land], or if weather was especially harsh. Animals died when predators found them to be a plentiful source of food.)
- Have students calculate the population density for each year provided in Table 1. It might help students to tell them that 10,000 square meters is roughly the size of two soccer fields.
- If students have already begun constructing biodomes in conjunction with this unit, have them determine the plant and/or insect population density of their biodome.
- For lower grades, students should be able to complete the activity, but may need a bit more support doing the calculation and in understanding the units.
- For upper grades, remind students to be aware of the units when doing the calculations.
Bush, Mark B. Ecology of a Changing Planet, Second Edition. Saddle River, NJ: Prentice Hall, 2000.
Dictionary.com. Lexico Publishing Group, LLC. Accessed October 9, 2006. (Source of some vocabulary definitions, with some adaptation) http://www.dictionary.com
World Population Trends, World Population Information. Last modified August 24, 2006. Population Division/International Programs Center, U.S. Census Bureau. Accessed October 9, 2006. http://www.census.gov/ipc/www/world.html
Christopher Valenti, Malinda Schaefer Zarske, Denise Carlson
© 2006 by Regents of the University of Colorado.
Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder
Last modified: February 5, 2016