In this lesson plan, adaptable for grades 3-12, use an interactive simulation to explore the relationships between perceived color and light.

Students will:

  1. Understand that light is made of photons
  2. Understand that filters block all light except the color of the filter
  3. Explore how red, green, and blue light combine to create perceived colors


  • Computers or other devices with Internet access
  • Interactive whiteboard


This lesson features an interactive simulation titled Color Vision, developed by our award-winning partner PhET through the University of Colorado Boulder.  The simulation invites students to explores the relationships between color and light.

Watch the Color Vision video primer for an introduction to the Color Vision simulation’s features and uses. Then review the Color Vision Simulation Overview to learn about the sim controls, model simplifications, and prompts to challenge student thinking.

Preview and play with Color Vision to plan how you will adapt it to your students’ needs. The Single Bulb are two separate instances within the same simulation, but they fit well together and students should be able to go from one to the other seamlessly.

For older students (high school physics), you can vary the vocabulary you use to describe elements of the simulation. For example, in the Single Bulb you can describe choosing the purple bulb as selecting a “short wavelength color.” In the RGB Bulbs instance, you can tell students to vary the intensity of each of the flashlights. For more advanced topics that older students may explore, see Extension Activities.

Students may explore the sim individually or with a partner.  

Build background knowledge or reinforce topics with these BrainPOP movies:  Color, Light, Rainbows, and Electromagnetic Spectrum.

Lesson Procedure:

  1. Play the BrainPOP movie Color on a whiteboard or other display. Explain that this lesson features additive colors (color and light).
  2. Open the Color Vision sim and click the Single Bulb. Show students how you choose a color and click the red button on the flashlight to turn it on. Demonstrate how to toggle  between white light and single colored light.
  3. Now model how to switch between the beam and photon view. Explain to students that light is composed of very special particles called photons that have both beam (wave) properties and particle properties.
  4. At their own computers or devices, have students open the Color Vision sim and invite them to explore with the filter. Ask them to write a sentence describing what the filter does. Then have students share their descriptions with each other.
  5. Now give students time to explore the RGB Bulbs. Challenge them to create specific colors using the three color flashlights.
  6. After creating these colors, have students write a short reflection on any relationships they have seen/tested while exploring the sim. Sample answers may include for example, “equal amounts of red, green, and blue produce varying shades of gray.”

Extension Activities:

Red, green, and blue are the primary “Additive Colors” and cyan, magenta, yellow, and black are the primary “Subtractive Colors.” Using what you have learned from the simulation, explain why red, green, and blue are additive. Infer what this means about the subtractive colors.
Filed as:  Color Vision