*Students track the goods and services they use for one week. Then they calculate and illustrate a personal water footprint. *

### PROCESS:

- As a class, review the diagram at the end of the article. Guide students to understand that the diagram shows the amount of water wasted when people toss out different kinds of foods.
- Display the Water Footprint Network's personal water footprint calculator. As a class, calculate the water footprints of a man and a woman who live in the United States, are average meat consumers and have a gross yearly income of $50,000. Compare the results.
- Instruct students to select new data to enter into the calculator. Review their choices to make sure there are no repeats. Then have students tally their results. Note: For older students, you may wish to use the extended version of the personal calculator instead. For detailed instructions on how to complete this activity, see the grade-level lessons below.
- Challenge students to create a diagram that illustrates their results in a way the average consumer can understand.

### ASSESSMENT:

Invite students to share their diagrams with the class. Compare the results. Discuss how various factors impact the size of a person's water footprint.

### CUSTOMIZE THE LESSON:

**Grades 3-4**:

Have the class complete the activity in small groups. Make sure each group has unique data to investigate. As a class, brainstorm ideas for diagrams that students could create to illustrate their results. Encourage each group to select the design it prefers.

**Grades 5-6:**

Have students complete the activity with a partner. Make sure each pair has unique data to investigate. Challenge partners come up with their own ideas for a diagram that illustrates their results in a way the average consumer can understand.

**Grades 7-8:**

Display the Water Footprint Network's personal calculator-extended. Explain that the purpose of this calculator is to help people assess their own unique water footprints. To illustrate how the calculator works, complete the personal calculator as a class to assess students' best guess of the average student's water footprint. If necessary, help students convert the amount of various foods eaten from kilograms into pounds. (One kilogram equals 2.2 pounds.) Then have students tally their own water usage for one week. Invite students to enter their data into the personal calculator to obtain their own water footprint. (NOTE: The last question on the calculator asks students to input their gross yearly income. To avoid divulging personal family information, you might want to have all students enter the same dollar amount.) Have students create a diagram that maps their individual results. As students present, compare their findings to students' "best guess" from one week before.

**Grades 9-10:**

Display the Water Footprint Network's personal calculator-extended. Explain that the purpose of this calculator is to help people assess their own unique water footprints. Then have students tally their own water usage for one week. Invite students to enter their data into the personal calculator to obtain their own water footprint. If necessary, help students convert the amount of various foods eaten from kilograms into pounds. (One kilogram equals 2.2 pounds.) (NOTE: The last question on the calculator asks students to input their gross yearly income. To avoid divulging personal family information, you might want to have all students enter the same dollar amount.) Have students create a diagram that maps their individual results.