877-542-5504 877-542-5504

How Much Water Can We Save While Brushing Our Teeth? Lesson Plan

Want to Help Fellow Teachers?

Please help us grow this free resource by submitting your favorite lesson plans.

Lesson Plan #: AELP-MPS0016
Submitted by: Casey Izzet
Email: degrc6l0@numen.elon.edu
             Elon College, North Carolina Date: May 10, 1999

Grade Level: 3, 4, 5


  • Mathematics/Process Skills
  • Science/Ecology

Duration: 2 hours Description: Students will learn how much water they waste by leaving the water running when brushing their teeth in a day. They will also use the data that they collected to create a number of graphs. Activities can be extended to focus on water conservation and ecology, or on healthful dental habits.

Goals: Students will actively engage in research by collecting data, analyzing it, representing it in the form of two types of graphs, and discuss findings.

1. Students will be able to show data collected as a class in a variety of ways.
2. Students will be able to demonstrate their ability to create, read, and interpret graphs.
3. Students will become familiar with two types of graphs: bar graphs and stem-and-leaf graphs.


  • new toothbrushes (your local Health Department will give them to you for free)
  • toothpaste
  • construction paper
  • roll of butcher paper
  • scissors
  • rulers
  • information data recording sheets

1. Split the students up into pairs. One will brush his teeth while the other keeps a record of the time taken. Then they will switch, so that each student has a time recorded (review the clock and how to time if necessary). 2. Show the students examples of quarts, and explain how many quarts were wasted if they brushed their teeth for a minute, etc.
(Experiment at home to find these numbers out…I found that four quarts were wasted each minute).
Have them convert the amount of time they actually brushed their teeth into the number of quarts wasted.

3. Give the students construction paper, ruler, and scissors. Tell them to cut strips of paper that show one inch per quart wasted.

4. Roll out the butcher paper and have the students paste their strips down on the paper. As a class, title it and mark the inches. This will be the class bar graph. (They love making their part themselves).

5. Use the students’ same data to construct a stem and leaf graph. Have the students write each digit of the number of quarts wasted in a day on a separate square of construction paper. Have them individually come up and tape their numbers on a large sheet of paper. They will learn through discovery how a stem-and-leaf graph works.

6. Focus on the theme of water conservation by discussing it in class. Have the students write a story about what they would do if they turned on their faucets and no water came out one day (or a similar theme).

(This is all that I had time to do in my class. The data could be further used to make pie graphs, line plots, etc.)

Assessment: By individually making the graphs and discussing their purpose, students should be able to demonstrate in class whether or not they are grasping the concepts.

Useful Internet Resource:
This lesson plan was adapted from a similar one on the Houghton-Mifflin lesson plan website entitled Water Wasters (in Spanish, Gastar El Agua). I modified it for use in a very large class with limited time resources.