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Why does the Moon change shape?
Spaceship Earth Unit | Lesson 5 of 5
Back > Share

Why does the Moon change shape?

Spaceship Earth Unit | Lesson 5 of 5
Lesson narration:
English Spanish
Scroll for prep
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DISCUSS:
What do you notice about the Moon each night? (1 of 14)

DISCUSS:
What do you notice about the Moon each night? (2 of 14)

DISCUSS:
What do you notice about the Moon each night? (3 of 14)

DISCUSS:
What do you notice about the Moon each night? (4 of 14)

DISCUSS:
What do you notice about the Moon each night? (5 of 14)

DISCUSS:
What do you notice about the Moon each night? (6 of 14)

DISCUSS:
What do you notice about the Moon each night? (7 of 14)

DISCUSS:
What do you notice about the Moon each night? (8 of 14)

DISCUSS:
What do you notice about the Moon each night? (9 of 14)

DISCUSS:
What do you notice about the Moon each night? (10 of 14)

DISCUSS:
What do you notice about the Moon each night? (11 of 14)

DISCUSS:
What do you notice about the Moon each night? (12 of 14)

DISCUSS:
What do you notice about the Moon each night? (13 of 14)

DISCUSS:
What do you notice about the Moon each night? (14 of 14)

Video trouble?

DISCUSS:

Before you start the activity, discuss as a class: what ideas do you plan to test to see if you can create the Moon’s phases and make them go in order?

Video trouble?
Video trouble?

Check out the video in the next slide to see your Moon phase model compared side-by-side with the real sky!

Video trouble?

DISCUSS:

Now that you've learned what causes the Moon's phases, how would you explain it to someone who doesn't know?

Anchor Connection

DISCUSS:

Look at the "Wonder" column of your class See-Think-Wonder chart.

  • Have any of your questions been answered by this lesson?
  • Do you have any new questions?

Slide Image
Slide Image

Moon


1 of 11

a large, round object in the night sky that can reflect the Sun's light
Slide Image

moon phase


2 of 11

the part of the Moon that we can see on a particular night
Slide Image

new moon


3 of 11

moon phase when the Moon looks completely dark
Slide Image

crescent moon


4 of 11

moon phase when the Moon looks like a sliver
Slide Image

half moon


5 of 11

moon phase when the Moon looks like half of a circle
Slide Image

gibbous moon


6 of 11

moon phase when the Moon looks like a little less than a full circle
Slide Image

full moon


7 of 11

moon phase when the Moon looks like a circle
Slide Image

pattern


8 of 11

something that happens again and again and again in a way that can be predicted
Slide Image

cycle


9 of 11

a set of events that repeats in the same order over and over

orbit (revolve)


10 of 11

to circle another object, like the Moon around the Earth
Video trouble?

model


11 of 11

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with
Video trouble?
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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
Venus & the Moon by Claude.schneider , used under CC BY-SA / cropped, adjusted color, added border
moon rising by flowcomm , used under CC BY / cropped, adjusted saturation, layered with another image
reaching for the moon by Sivaprasad k S / spliced
full moon by Krückstock , used under CC BY-SA / adjusted saturation
harvest moon rising by slworking2 , used under CC BY / adjusted color and speed
moon in daylight by Zeynel Cebeci , used under CC BY-SA / adjusted color and cropped
moon in sky by Bill Johnston / cropped, layered with other imagery
crescent gibbous moon by Thomas Bresson , used under CC BY / Heavily modified
crescent moon by P. Bramwell / Heavily modified
moon view by Luc Viatour , used under CC BY-SA / Heavily modified
house at night by StruffelProductions / cropped
sunrise background by Stellarium / Heavily modified
tablet by simon-ho / Heavily modified
lightbulb by KMJ , used under CC BY-SA / Heavily modified
Earth by Celestia / part of a diagram
Other
crescent moon by Richard Flink , used under CC BY-SA / cropped, adjusted color
Credits
Lesson narration:
English Spanish

Grade 5

Earth & Space Patterns

Moon Phases, Lunar Cycle

5-ESS1-2

11907 reviews

Activity Prep

Print Prep
This lesson explores why the Moon seems to change shape (phases) over the course of a month. In the activity, Model the Moon's Phases, students use a styrofoam ball as a model of the Moon and a flashlight as a model of the Sun to gain a better understanding of how the interactions between the Sun and Moon are responsible for the Moon’s phases.
Preview activity

I have a Mystery Pack

Pencil
Sharpened. Skewers also work.
Details
15 pencils
Bright Flashlights
You can also use a bright lamp or overhead projector that you can point towards the students to serve as the Sun for multiple groups. Be careful not to look directly into such a bright light source.
Details
15 flashlights
Styrofoam Balls (2")
We suggest smooth, solid styrofoam balls. Rough foam balls are translucent and don't work as well. You can substitute any round opaque object that can be skewered.
Details
15 balls
Prep Instructions

We suggest students work in pairs. Homeschool students will need a partner for this activity.

Prepare to Darken the Room

It is important to get your room as dark as possible! It's worth taking the time to black out your windows and even tape curtains to eliminate cracks of light. Also, the brighter your flashlights, the better the demonstration. The flashlights we link to are particularly bright and inexpensive.

Exploration

13 mins

Hands-On Activity

25 mins

Grade 5

Earth & Space Patterns

Moon Phases, Lunar Cycle

5-ESS1-2

11907 reviews
Slow internet or video problems?
Credits
 
Astronomy Lesson 5: Why does the Moon change shape?

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