Spanish Version

Water Wasters

Math Activity

Students will be surprised by how much water they can save if they brush their teeth without leaving the water running.


  • Clean, empty one-quart milk cartons
  • New toothbrushes
  • Toothpaste


  1. Have students work in groups of three for this activity.

  2. One student brushes his or her teeth with the water running.

  3. Another student fills containers with the running water until the toothbrusher has finished.

  4. The third student keeps track of how many quart containers are filled.

  5. Use the information from this activity to solve some math problems, which will in turn help students visualize how much water can be wasted on a daily task.

How many quarts of water does your family use for brushing teeth each day?

Possible solution:
Students may break the problem into the following steps:

  1. Multiply the number of family members by the number of times each person brushes his or her teeth per day.

  2. Then multiply the result by the total number of quarts of water the student group collected during one brushing.

You may download, print and make copies of this page for use in your classroom, provided that you include the copyright notice shown below on all such copies.

Copyright © 1997 Houghton Mifflin Company. All Rights Reserved.