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Explore and Play: Red Light, Green Light

Color is the key to this stop-and-start game.


  • red light and green light signs—red and green colored paddles
  • yellow paddle
  • flashlight

Key Science Concepts

  • A single color can have different shades, from very light to very dark.
  • After passing through a transparent colored material, the color of the light looks like the color of the material.


Tell children they are going to play a game they might already know, called Red Light, Green Light.

  1. The game can be played indoors or outdoors. Have children line up at one end of the space facing you.
  2. Say “Green Light!” and hold up the sign. The children walk quickly towards you.
  3. Then say “Red Light!” and hold up the red sign. The children stop where they are.
  4. Continue saying “Red Light!” or “Green Light!” until the children reach you. Then start over again.

Share and Reflect

In a circle, hold up the red and green paddles. Then turn on the flashlight behind the red light, then the green light. Ask children what the difference is between how the colors look with and without the flashlight. Ask them why they think real traffic lights have lights behind them. Tell them that sometimes colors have meanings. Ask them what the red and the green of a traffic light means. Then show them the yellow paddle, and shine the flashlight behind it. Ask them what they think the yellow light means.