Academic standards correlations on Teachers' Domain use the Achievement Standards Network (ASN) database of state and national standards, provided to NSDL projects courtesy of JES & Co.
We assign reference terms to each statement within a standards document and to each media resource, and correlations are based upon matches of these terms for a given grade band. If a particular standards document of interest to you is not displayed yet, it most likely has not yet been processed by ASN or by Teachers' Domain. We will be adding social studies and arts correlations over the coming year, and also will be increasing the specificity of alignment.
Although over 70% of Earth's surface is covered with water, less than 1% of this water is available for human consumption. In this lesson, students study the availability of water on Earth and discuss methods that can be used to purify and conserve this critical resource. They also assess how much water they and their families typically use, and think about ways to reduce their water usage. Finally, students explore different techniques being employed for water management around the world, including the use of dams to create reservoirs.
Two to three class periods
1. Tell students that you would like them to think about the answer to this question: What percentage of Earth's water is available for human consumption? Ask students to write down their answers. You may want to remind students to consider what they know about oceans and about the type of water that is considered usable by people.
2. Ask a volunteer to demonstrate his or her answer to the question. Give the student a 2-liter bottle filled with colored water and a clear, empty container. Tell the class that the bottle represents all of the water on Earth. Ask the volunteer to pour into the empty container the amount of water that he or she thinks represents the percentage of Earth's water available for human use. (Provide the student with a measuring cup if needed.) Then ask the class to make suggestions about whether more or less water needs to be in the container. Have the volunteer adjust the amount until there is a general consensus among the students. Put the class estimate (the clear container with water) aside.
3. Tell students that you will now demonstrate the amount of water on Earth that is available for human consumption.
Note: You may also want to place a fresh water sign on the table at this time. As you pour off additional amounts of water in steps c-d, you can place the new containers near the fresh water sign to remind students that each one is part of the "fresh water" category.
4. Divide the class into small groups and ask them to discuss what they just witnessed in your demonstration and in the interactive activity. (You may want to review the terms renewable resource and nonrenewable resource as a class before placing students into their groups.) Have students answer the following questions during their small-group discussions:
5. Bring the class back together and ask student groups to share some of their ideas. Conclude by reminding students that water is necessary for life and thus important to conserve and maintain so that it stays available for human consumption, as well as for consumption by plants and animals, which people use for food.
6. Watch the Water Treatment Plant QuickTime Video and discuss the methods used to purify water for human consumption. Ask students the following questions:
7. Show the map of your local watershed. Help students trace the path of water to their school. Discuss the following questions:
8. Distribute the Water Use Worksheet PDF Document, and ask students to estimate the amount of water that they and their families typically use in a week.
9. Watch the Conserving Water at Home QuickTime Video. Discuss water conservation techniques that people can use to decrease the waste and pollution of our water resources. Consider the following questions:
10. Divide the class into small groups again and ask them to brainstorm ways that they and their families can conserve water. After the small-group discussions, bring the class back together and ask each group to share their top three ideas with the class.
11. Increases in population and industrial growth are straining water resources around the world and making the need for water management more urgent. Show students the Water Conservation: Israel QuickTime Video and the Water Conservation: Mexico QuickTime Video. Discuss the following questions:
12. Divide the classroom into two groups. Assign one group to develop arguments in support of the use of dams to manage water for large cities. Assign the other group to develop arguments against it. Show the Water Conservation: Denver, CO QuickTime Video, and then have the two groups debate the pros and cons of using dams.
13. Show the class the local watershed map again and label the location of any dams in the area. Discuss the following questions:
Have each student write an article or editorial discussing his or her ideas about one of the following topics. Let students know that they will need to support their ideas using information they learned from the multimedia resources. You may also want to encourage students to conduct additional research online and/or seek out individuals in the community to interview about local efforts regarding their chosen topic. (Note: You can have students submit their pieces to a school or other newspaper.)
The Digital Library for Earth System Education (www.dlese.org) offers access to additional resources on this topic.