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Hi all, 

I am creating a 2 week block plan on our solar system and one of my days focuses on the phases of the moon and why it changes shape. I was thinking about using a flashlight activity with a globe and a white piece of paper to represent the moon. The flashlight (represents the sun) will be places in a stationary spot and the globe will be placed about five feet away. I will be holding the paper and have it slowley rotating around the globe to represent the moons orbit around Earth while the students observe the shadows earth casts on the moon while it orbits. Is there any other activity I could do for the students to be able to physically see why the moon changes shape?

Hi Elizabeth, 

You don't say what age children you will be teaching, or what their prior experience is with observing and creating shadows. Giving children plenty of experience with creating and understanding shadow formation will help them understand how shadows change the way the moon appears to us. Children may not understand the relationship between the source of light and the object it shines on and the cast shadow. 

If children have time to play with flashlights before participating in the modeling of the Sun-Earth-Moon system, they will have had time to try their own ideas before focusing on this one.

Best wishes,

Peggy

I assume someone has already mentioned this to you, but the moon's phases are not caused by the Earth's shadow on the moon. It is the amount of the lit side of the moon we get to see. Half of the moon is alays lit(except for a solar eclipse) what changes is the amount of the lit side we get to see. if you use a bright light for the sun and a sphere for the moon and put a student in the center of the moon's orbit they will see that they see the varying parts of the moon's lit side as it revolves around them.

Bruce

Great point Bruce, our misconceptions, or first ideas, are hard to change because they seem so logical based on limited experiences. Open-ended exploration of light and shadow formation, followed by first hand experience using the materials in the 'Teaching Moon Phases' lesson plan Emily suggested (by Deborah Scherrer of the Stanford University Solar Center, originally developed by Dennis Schatz, Pacific Science Center) can lead to that 'ah-ha' moment understanding what causes Moon phases activity.

Hello,
 

I think this would be a great activity to show your students. You can also have the students observe the moon for a full cycle and draw the picture of moon in a notebook so they could see the different phases of the moon.  I did this with my class, and they enjoyed observing the moon.
 
Good Luck!