Target Grade Level / Age Range:



30 minutes


Students will explore humans’ demands on the world’s water supply and discuss ways to conserve it. 


  • Clear container with wide mouth opening
  • At least 4 sponges cut into 8 inch pieces
  • Water
  • Markers
  • Paper towels
  • Chart paper
  • Bowl

Suggested Companion Resources:


  • Limited resource – a set amount of a necessary resource that can be all used up

Background – Agricultural Connections:

Water is an essential part of agriculture. Both crops and livestock require water to live and adequate amounts of water to thrive. Agriculture is a huge user of water, making it imperative that the water that is used is not wasted. Farmers also have to be cautious when using fertilizers and chemicals to not pollute groundwater. Because water is a limited, non-renewable resource, farmers are careful to use minimal amounts of it to ensure that animals and crops are hydrated but water is not wasted.

Interest Approach or Motivator:

Tell students that water is a limited resource, meaning we only have a set amount of it and it can be used up. Ask students to think of ways water is used throughout the day, starting with the morning and ending at night. Record student responses on the chart paper. Examples may include showering, brushing teeth, drinking water, water in windshield washer fluid in the car, water used to cook meals, water used to produce plastic products, water used to grow food, etc.


  1. Cut the sponges so there is an 8-in piece for each water use. Tell students that the sponges represent the water that is used up by that function and must either be treated be used again or cannot be used again.
  2. Place the clear container filled with water on the floor or a table in front of students. Mark the starting water level in the container.
  3. Ask a student to place a sponge in the container for the first listed water use. Have students watch as the sponge “uses up” some of the water in the container.
  4. Continue to have students add sponges to the container until all of the uses are represented by a sponge in the container.
    1. Ask students: are these all the uses of water? Do you think there may be more that aren’t listed?
    2. How did the sponges effect the water level in the container?
    3. Can the water that has been used up be reused?
  5. Gently remove the sponges from the container without squeezing and place them in the bowl. Lift the container to show students the remainder of the water. This represents what happens if we use water carelessly – it will all be gone!
  6. Discuss with students ways that water can be conserved by both students. Examples could include:
    1. Taking shorter showers
    2. Taking showers instead of baths
    3. Turning water off when brushing teeth
    4. Collecting rainwater in a rain barrel
    5. Not watering lawns and gardens
  7. Explain to students that agriculture uses a lot of water, but that water is necessary to produce food to eat, clothes to wear, and fuel to power cars and trucks. What are some ways that farmers can still meet the needs of their crops and livestock while maintaining a clean and safe water supply?
    1. Farmers manage nutrients from fertilizers and animal wastes by storing them correctly and only applying them in small amounts when necessary
    2. Farmers can keep animals in barns as opposed to in pastures where they can stand in creeks and pollute water
  8. For each conservation or water reduction method, squeeze a sponge back into the container. Ask students to observe, and notice that while the water level rises, it never reaches the initial level of the water in the container. Ask students to talk with a partner or write about why they think that is.

Did you know? (Ag facts):

  • Did you know that the U.S. uses: 39% of freshwater for irrigation and growing food, 48% of freshwater for industry, and 13% of freshwater for domestic use (showering, laundry, etc.)
  • The daily drinking-water requirements per person are 2-4 litres. It takes 2,000 – 5,000 litres of water to produce a person’s daily food.

Extension Activities:

Have students keep a journal over the course of a week. Have them track the number of minutes the spend with water running brushing their teeth or taking a shower. Challenge them to reduce that time to conserve fresh water.


Adapted from Nikki Thies, Polk County teacher


Kelsey Faivre

Organization Affiliation:

Iowa Agriculture Literacy Foundation

Agriculture Literacy Outcomes:

  • Agriculture & the Environment Outcomes:
    • Describe the importance of soil and water in raising crops and livestock
    • Identify natural resources
  • Plants and Animals for Food, Fiber and Energy Outcomes:
    • Identify the importance of natural resources (e.g., sun, soil, water, minerals) in farming
  • Food, Health and Lifestyle Outcomes:
    • Recognize that agriculture provides our most basic necessities: food, fiber (fabric or clothing), energy, and shelter

Iowa Core Standards:

  • K-ESS3-1. Use a model to represent the relationship between the needs of different plants or animals (including humans) and the places they live.
  • K-ESS3-3. Communicate solutions that will reduce the impact of humans on the land, water, air, and/or other living things in the local environment.

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