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Global Atmospheric Change

Author(s): Nancy Moreno, Barbara Tharp and Judith Dresden

Prisms and Rainbows


  1. Fill a clear, liter-sized glass or plastic container with water and place it on the lighted “stage” of an overhead projector.

  2. Darken the classroom as much as possible. You and your students will be able to observe a circular rainbow projected around the classroom.

  3. Allow a few moments for students to observe the rainbow. Ask, Have you ever seen anything like this before? Students will provide a variety of responses. Follow by asking, Do you think the colors are the same in every rainbow?

  4. After students have shared or written their predictions, place another, smaller cup or glass filled with water on the overhead. Have students observe and compare the sequence of colors in the rainbow produced by the second cup.

  5. Repeat with a second cup or glass of water. Repeat the question, Do you think think the colors are the same in every rainbow? Make sure students are able to observe that the sequence of colors always follows the same pattern. With older students, explain that the colors of light represent energy of different wavelengths.

  6. Have students identify the source of light for the rainbow (white light from the overhead projector). Then, help them understand that the light is being separated into its constituent colors as it passes through the water in the container. 

  7. Let each student make his or her own “rainbow” drawing that incorporates the sequence of colors observed in the classroom rainbow. Display the rainbow drawings. 

Funded by the following grant(s)

National Institute of Environmental Health Sciences, NIH

National Institute of Environmental Health Sciences, NIH

My Health My World: National Dissemination
Grant Number: 5R25ES009259
The Environment as a Context for Opportunities in Schools
Grant Number: 5R25ES010698, R25ES06932

Houston Endowment Inc.

Foundations for the Future: Capitalizing on Technology to Promote Equity, Access and Quality in Elementary Science Education