Target Grade Level / Age Range:
Students will learn about the ways in which water can become polluted, ways to conserve it, and why it is important to conserve water.
- A clear plastic washtub big enough to hold several gallons of water (a clear plastic storage container would work well)
- Enough clean water to over halfway fill the plastic washtub; one gallon separate
- A bottle cap
- Slotted spoon
- Other tools useful for moving small items
- Laundry soap
- Vegetable oil
- Small pieces of paper
- Small pieces of trash and food
- Food coloring
- Rocks and soil
Suggested Companion Resources
- Water Sources Use Conservation by Nancy Carlson
- Conservation – preservation, protection and restoration of the natural environment
- Stewardship – the act of protecting or being responsible for something
- Pollution – the introduction of something into the environment that has harmful or poisonous effects
- Irrigation – using water that is not rainfall to provide water for crops and animals.
Interest Approach or Motivator
This hands-on visual demonstration will allow students to see firsthand the amount of useable water on Earth and the damage humans can do to it.
Background – Agricultural Connections
Agriculture is highly dependent on water. Crops need it to grow, livestock need it to live, and farmers rely on it to carry on farm operations such as sanitizing milking parlors and cooling milk.
- Have students read the book Water Sources Use Conservation by Nancy Carlson.
- Have students discuss water based on the book they’ve read and their own personal knowledge. Make sure to acknowledge that water is one of the most important things humans need to live, but most water isn’t available for our use! Much of it is salt water or frozen. 70% of the Earth is water, but only 1% of that is useable.
- Present a gallon of water to represent all of the water on earth. Then, fill a bottle cap with the water from the gallon. The bottle cap represents how much water on Earth is available for us to use.
- Have students discuss ways to save water in their everyday lives. With such a small percentage of the water on Earth being useable, it is important to conserve it! Some ideas may include:
- Whenever you wash your hands, don’t leave the water running. Wet your hands and turn the water off. Use soap and lather your hands well, then turn the water on to rinse. Turn off the water and make sure it is off completely. Then dry your hands.
- Do the same when you brush your teeth. Turn the faucet on to get your toothbrush and toothpaste wet, and then again to rinse your mouth and toothbrush. Don’t leave the water running while you’re brushing.
- Tell People! Tell your friends what you’re doing and why and encourage them to do the same. Tell adults when faucets are dripping. Is there a leaky faucet or toilet in the bathroom at school? Be sure to let someone know so that it can be repaired.
- Since baths use a lot of water (about 37 gallons on average), take short showers instead and use only about 20 gallons of water, instead.
- Use a wastebasket for used tissues, or things like gum wrappers, paper towels, or even dead bugs or goldfish. Don’t flush them – the average flush uses as much as 5 gallons of water!
- Do you have plants in your house? When meals are prepared and vegetables or other fresh produce are washed, collect that water and use it to water the plants.
- Do you like a drink of cold water now and then? Rather than running the kitchen faucet for several minutes to get cold water, keep a pitcher of water in the refrigerator.
- Put a barrel outdoors to catch rain water, then use that water for things like watering plants and save hundreds of gallons of water a year!
- In the summertime, it’s fun to play under the lawn sprinkler. When you do, make sure it’s when the lawn is being watered evenly at the same time.
- Do you have other summer water toys that require a running hose? These might be fun, but they also waste gallons and gallons of water.
- If the adults in your home occasionally water the lawn, encourage them to water in the cooler parts of the day (early morning, or at or after sunset), and never on windy days. This keeps in the soil all the water being sprayed instead of most of the water being lost to evaporation.
- Fill a clear washtub with water and place in the center of the classroom. Have students circle around the washtub, and tell them a story, starting with the tub representing a crystal clear, clean lake. The fish that live in the lake are happy, humans can swim in it, and mammals can drink from it. However, people keep coming to the lake and polluting it! You and I are very dependent on the water from this lake. What might we need it for? Farmers who farm close to the lake rely on it as well. Why might they need it?
- Set out the salt, food coloring, paper, trash pieces, vegetable oil, soil and rocks, and laundry soap out. Have students choose an item, add it to the washtub, and tell the story that matches it:
- Vegetable oil: (Student’s name who chose item) works as a mechanic in car repair shop. He spends a lot of time changing the oil in cars, so he has a lot of used engine oil. It costs a lot of money to properly dispose of the oil, so he dumps it in the lake instead. Is this good for the lake?
- Salt: Let’s pretend this salt represents fertilizers that are used on golf courses, lawns, and farm fields. They are important for helping grasses grow, but sometimes can travel down through the soil and end up in water, like our lake.
- Food coloring: Chemicals are used a lot in America. We use them to do many things, but often need them to keep insects and weeds off of our lawns, golf courses and farm fields. Just like fertilizers, these chemicals can travel through the soil and get into our water, like the lake.
- Laundry soap: (Student’s name who chose item) owns a laundromat next to the lake. Sometimes, soaps and suds leftover from her washing machines drain into the lake.
- Trash: a family comes to the lakeshore to have a nice picnic, but it’s a blustery day. The trash from their picnic flies away in the wind and ends up in the water.
- Paper: while driving by the lake, (student’s name who chose the item) had his/her windows down. A gust of wind blew several receipts from stores and a letter into the lake.
- Soil and rocks: The biggest pollutant of our water is soil! (Student’s name who picked the item) lives close to the lake. He/she recently removed the trees and shrubs bordering the lake, so now when it rains, the exposed soil runs into the lake! This can clog fish gills, stop underwater plants from photosynthesizing, and smother smaller water dwelling creatures.
- Have students examine the washtub in its polluted state. Ask students if they think the water can still be used for drinking, swimming and living in. Why might the water not be healthy anymore? How would this impact the community and the farmers around the lake?
- Have students take turns with a utensil such as a slotted spoon or tongs trying to remove pollution from the lake. Students will notice that larger items are easily cleared away, but some can’t be removed from the water. That’s why it is important to take care of the water before it becomes polluted!
Did you know? (Ag facts)
- Some farmers use water for irrigation, where farmers artificially add water to their crops and soils to help crops grow in dry conditions. Many farmers in Nebraska irrigate their crops. Any type of crop may need irrigation, even in parts of the country that get plenty of rainfall. Cotton is an example of this. It is grown in the southeastern U.S., which gets plenty of rainfall, but the soils are dense and make it hard for plants to soak up water. So, cotton farmers irrigate!
- Dairy farmers use water to cool milk down rapidly. By running very cold water along the pipes that milk travels through, the milk is cooled. Then, many farmers water their cows with it.
- Explore with students possible water-related careers. These could include scientists, environmental scientists, leaders in organizations working to protect water, or teaching others how to use water conservatively.
East Pottawattamie County Farm Bureau
Agriculture Literacy Outcomes
- Plants and Animals for Food, Fiber & Energy Outcomes, 3-5. Science: Understand the concept of stewardship and identify ways farmers/ranchers care for soil, water, plants and animals