Activity time: 15 minutes
Materials for Activity
- A floor lamp with a bare bulb, and (optional) extension cord
- A large blue balloon, string, and thumbtacks (or painter's tape)
- A dowel or a long, flat tipped stick; a small, light ball (Styrofoam(TM) or a ping pong ball); and a glue gun
Preparation for Activity
- Plug in the floor lamp in a windowless corner, with space for you to walk safely around it.
- Glue the small ball to the end of the dowel.
- Blow up the balloon and use tacks (or tape) and string to suspend it from the ceiling, directly above the floor lamp.
- Read the Description of Activity. Practice using this set-up to throw shadows from the "moon" (the ball on the dowel) onto the surface of the "earth" (the blown-up balloon). Participants will need to see the shadows as you move the ball, in a circle, around the balloon. Make sure there is plenty of room to maneuver. Adjust the components as needed.
Description of Activity
The goal is to explore the phases of the moon.
Gather participants around the floor lamp and explain that the balloon represents Earth, the ball represents the moon, and the light bulb represents the sun. Using the stick, circle the "moon" around the "earth." Try it while standing in different positions. Invite the children to observe and describe the different shadows the moon casts on the earth.
Ask the children if they have ever seen a full moon, a half moon, or a quarter moon. They may be familiar with terms such as crescent moon, harvest moon, or "once in a blue moon." Invite them to look for moon shapes they know as you make different shadows.
Use these questions to lead a follow-up discussion:
- Imagine living thousands of years ago. What would it have been like for people who did not know the earth was round, or how the phases of the moon were formed? What would they think? What would they believe?
- Are you ever amazed by the sight of a full moon in the sky? Does understanding why you can see the whole moon make you more amazed, less amazed, neither, or not sure?
Optional: Have someone draw continents on the "earth" before it is suspended. Have someone else draw pockmarks on the "moon."