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Why does the Moon change shape?

Spaceship Earth Unit
Lesson 5 of 5
Moon Phases, Lunar Cycle
4.7 (12068 reviews)
Lesson narration:
English Spanish
Scroll for prep
Video trouble?

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?

Slide Image
Slide Image

Moon


1 of 12

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

moon phase


2 of 12

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

new moon


3 of 12

moon phase when the Moon looks completely dark
Slide Image

crescent moon


4 of 12

moon phase when the Moon looks like a sliver
Slide Image

half moon


5 of 12

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

gibbous moon


6 of 12

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

full moon


7 of 12

moon phase when the Moon looks like a circle
Slide Image

cycle


8 of 12

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

lunar cycle


9 of 12

the process of the Moon going through all of its phases
Slide Image

pattern


10 of 12

something can be observed again and again and again in a way that can be predicted

orbit (revolve)


11 of 12

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

model


12 of 12

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
Why does the Moon change shape?
Spaceship Earth Unit
Lesson 5 of 5
Moon Phases, Lunar Cycle
4.7 (12068 reviews)

Featured Reviews

“The sequencing of the phases of the moon when done with photos! Also, the mind-blowing photos of the universe on one of the enrichment activities. ”
· Mike · Teacher
“Loved the pictures of the moon phases and comparing them to what the moon looked like in the night sky. The kids really enjoyed the activity as well. ”
· Kristi · Teacher
“Terrific lesson!! Mystery Science always keeps my students engaged and thinking outside the box. We loved recreating the phases of the moon this week! My students are so excited to come to school each morning and let me know what phase of the moon they saw the night before!”
· Jackie · Teacher
“Great lesson that made students thinks about the phases of the moon. A simple lab yet I heard many students voice how "cool" it was to recreate the moon phases themselves.”
· Denise · Teacher
“The students enjoyed seeing and creating the different phases of the moon. It was great to hear them using the vocabulary from the exploration during the activity. ”
· Pamela · Teacher
“The kids were so excited to actually create the phases of the moon in the classroom. Just today we noticed the moon in the sky as we walked to lunch. My students were able to determine with great accuracy how many days we were into the lunar cycle just by viewing it. Quite impressive!”
· Stephen · Teacher
“The phases of the moon experience was a big hit! My students loved working in groups and of course, having the lights out was very exciting for them! They experimented with many different movements of the sun and moon. Lots of good thinking going on.”
· Beth · Teacher
“Fabulous information that prepared students for the investigation which deepened their understanding of moon phases.”
· Brenda · Teacher
“I liked how I was able to push the students to be more clear with explanations about the phenomenon. Many of them start with partial notions about how "the sun's light strikes the moon at a different angle." I liked how this activity made them step through the explanation more explicitly.”
· Alexander · Teacher
“The kids were totally engaged! Love how it walked them through step by step and showed them examples of what they should be looking for!”
· Shayna · Teacher
“My students loved the activity that went with the mystery. Having hands on activities help diverse students learn and understand how the moon phases happen.”
· Marisela · Teacher
“I enjoyed seeing and hearing the 'a-ha' moment from my students when they were able to understand why the moon changes shape based on where it is aligned with the sun. ”
· Stephanie · Teacher
“We have loved this unit. It really SHOWS students how it all works. Each activity is fun without too much hassle for me. ”
· Kristi · Teacher
“Oh my gosh! This was so much fun! My fifth graders loved it! Doug is so clear with his explanation about complicated concepts. Thanks, Doug!!”
· Connie · Teacher
“Watching our own phases of the moon! Our boys absolutely loved that activity! ”
· Terra · Homeschooler
“Students were very interested in the phases of the moon - something that was new for many of them. The activity was great - even I enjoyed participating!”
· Nicole · Admin
“video clips great visuals of the moon moving across the sky and slowly changing phase and position.”
· Kelsey · Teacher
“LOVED THIS! The kids had so many "ah-ha" exclamations as we did this lesson.”
· Whitney · Teacher
“The best part was that the model really worked! The kids loved it and were able to answer the assessment question at the end of the lesson after experiencing the lesson textually, visually, and through physical interaction. ”
· Pamela · Teacher
“My 5-year-old daughter always loves the activities that go with these lessons! This one was especially fun and her 3.5-year-old sister wanted to participate as well so they took turns being the moon and the sun. :) My daughter was able to complete the assessment, explaining in her own words, the answers to each question. She even got the first part of the challenge question correct! :)”
· Jennifer · Homeschooler
“The kids loved the activity and hands on explanation of why the moon changes. We threw in a couple more vocabulary words, such as waxing and waning. For the activity, we substituted a clementine as the sphere, so had all items on hand. Yay!”
· Jordan · Homeschooler
“My students have never been so engaged in Science before. Not to mention, it's so much less prep time than most Science activities! ”
· Jaclyn · Teacher
“The video clip that explained the activity was so helpful and so well done. The sequence of the moon's phases, displayed one after the other helped the students to clearly see how the moon changes.”
· Elizabeth · Teacher
“They really got it when we did the demonstrations\activity.”
· Johanna · Teacher
“The hands-on modeling of the moon phases made a huge impact on their understanding of why the moon looks the way it does.”
· Deb · Teacher
Lesson narration:
English Spanish

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

Vocabulary

Assessments

I don't have a Mystery Pack
In your Mystery Pack Lesson Bag
Styrofoam Balls (2") 1 ball per pair
In your Mystery Pack Shared Supplies
Bright Flashlights

The flashlights in the Mystery Pack have a piece of cardboard blocking the battery connection which needs to be removed before use.

1 flashlight per pair
Not included in your Mystery Pack
Pencil

Sharpened.

Skewers also work.

 1 pencil per pair
Prep Instructions

We suggest students work in pairs.

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.

Standards

Jump to

Exploration

13 mins

Hands-On Activity

25 mins

Wrap-Up

7 mins

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Credits
 
Astronomy Lesson 5: Why does the Moon change shape?

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