Lunar Cycle

What You Need


  • One lamp
  • One globe
  • One small ball the size of a softball
  • Glue
Lunar Cycle


To familiarize students with repeating patterns in nature, namely the phases of the Moon.


The activities in this lesson involve both individual and class work to facilitate students' learning about the predictability of the moon's phases. Beginning with a hands-on activity to give students a tangible demonstration of the moon's orbit and rotation, this lesson incorporates student observation, documentation, and online activities which encourage students to recognize the pattern of the moon's phases. Class discussions encourage students to understand the lunar cycle as one example of a pattern that we can find in nature. The discussions further challenge them to consider other patterns in nature as well. While students "from the earliest grades should be asked to look for regularities in events, shapes, designs, and sets of numbers" (Benchmarks for Science Literacy, p. 217.), their learning at the K-2 level “…about objects in the sky should be entirely observational and qualitative…The priority is to get the students noticing and describing what the sky looks like to them at different times…But it is too soon to name all the moon's phases and much too soon to explain them." (Benchmarks for Science Literacy, p. 62.)

At this point of their development, you can expect that students have noticed the moon before, and perhaps even noticed the different ways the moon can look (full moon versus crescent moon, for example). They will also know that they see the sun during the day and the moon at night. This lesson builds upon their general observations and familiarity with the moon yet challenges them to make keener observations as they document what the moon looks like each evening. Keeping a daily record of the moon's appearance, students develop a calendar which records a full lunar cycle. Recording the moon's appearance each day over a period of a month serves as a foundation for later learning about the lunar cycle and other cyclical patterns in nature. As Benchmarks for Science Literacy states, "There are many ways to acquaint children with earth-related phenomena that they will only come to understand later as being cyclic…students can start to keep daily records of (phenomena) and plot them by week, month, and year." (Benchmarks for Science Literacy, p. 67.)

This lesson offers activity ideas and discussion questions to facilitate students' learning that "the moon looks a little different every day, but looks the same again about every four weeks." With an approach that supports students' observational and qualitative exploration of these concepts, students learn that the lunar cycle is but one of many patterns we can find in nature and the universe.

Planning Ahead

You will want to visit the Lunar Cycle Calendar site ahead of time to print out both blank copies of the calendar and sets of the main phases of the lunar cycle. (You can find the main phases by clicking on the button that says "Go to Lunar Cycle" and then on "Go to Main Phases.") Cut these out for students to order into a lunar pattern.

Earth-Moon-Sun Dynamics is a brief yet comprehensive overview of the lunar cycle that you may refer to as a teacher resource in preparation for this lesson.


To engage students' curiosity about the moon and to help build a foundation for learning about the pattern of moon phases, consider beginning with a simple hands-on activity that models the orbit of the moon in relationship to the earth and sun.

Place a large lamp (without the lampshade) in the center of the room. Make sure the classroom is dark, except for the light from this lamp. Position a globe a short distance from the lamp. Ask students to imagine that the lamp is the sun and the globe is the earth. (While many students will be familiar with the earth, some younger students may not be. For the purposes of this lesson, you can explain to students that the earth is the place where we all live.) For the moon, one student can hold a ball-shaped item that is smaller than the globe yet large enough to observe, such as a softball, and walk around the globe. Students will be able to observe the change in light and shadow on the moon (ball) as it travels around the earth (globe). As the moon travels around the earth, students also will be able to observe that although the amount of light and shadow on the moon changes, it changes the same way each time the moon travels around the earth, creating a pattern. Let more than one student have an opportunity to hold the moon. You could also allow students to switch positions each time the moon orbits the earth to give them different vantage points of the moon as it moves. Consider asking students these questions to facilitate these types of observations:

  • What do you notice about the moon?
  • How much of the moon can you see?
  • How much of the moon is dark?
  • Is there any time that the moon is completely dark?
  • Is there any time that the moon is in completely light?
  • (Have the moon travel around the earth several times to allow time for observation.) What do you notice when the moon goes around the earth again?

Open-ended questions will encourage students to focus their observations on what is happening. In this part of the lesson, simply collect students' responses. Accept all statements without correction. Beginning with the students' observations and ideas is an excellent starting point for learning more about the cyclical pattern of moon phases because it builds on their interest and excitement about this topic. As the lesson develops, students will learn more about the lunar cycle. You can help them reevaluate their initial thoughts as you teach the lesson.


Students are now ready to observe the moon in a more focused way. In this part of the lesson, students use their observation and documentation skills to record the moon's changing appearance. By the end of this activity, they will be able to recognize a pattern in the moon's changing appearance.

Tell the class that they each will have a turn to be a Moon Observer! Each day, ask one student to be the Moon Observer. Using The Moon I See student sheet, ask the Moon Observer to look at the moon that evening and draw what the moon looks like. The next day, ask the student to share her/his observations with the class, and display the Moon I See student sheet in the classroom. (Note: If it is overcast for a period of time, it will be difficult for students to observe the moon. One option for dealing with this challenge is to have students draw what they see anyway. They are still observing what actually happens. When they are able to see the moon again more clearly, challenge them to consider how the moon might have looked during those overcast days. By looking at the last day they could see the moon and the first day they could see the moon again, they will have good information for helping them think about the phases that were in between. Another option is to have students fill in the missing phases later in the activity when they have had more exposure to the different phases.)

Distribute the blank Lunar Cycle Calendar. Ask the whole class to record the Moon Observer's observation by replicating it in the corresponding day of the calendar. As students take turns being the Moon Observer, display their student sheets in sequential order. Students' calendars should correspond to the display of student sheets. When you have recorded the moon's appearance for about two weeks, lead a class discussion to facilitate student recognition of an emerging pattern. Consider questions like:

  • What did the moon look like on the first day?
  • What did it look like at the end of the first week?
  • How does it look now, at the end of two weeks?
  • What do you notice about the amount of light/dark of the moon each day?
  • What do you think it will look like tonight? Tomorrow night?

To help students recognize that "the moon looks a little different every day, but looks the same again about every four weeks," have them use the Moon Phases student esheet to go to the Lunar Cycle Calendar website. The calendar used earlier will appear, but on the right-hand side students can “Go to Lunar Cycle” where they can see images of a full lunar cycle and images of the main phases.

You can choose to either have students use the esheet at the two-week point or wait until students have completed a full calendar. Doing it at the two-week point will allow students to see an emerging pattern and challenge them to make predictions, as well as offer them a context of the patterned lunar cycle for their remaining observations. Waiting until the completion of one full lunar cycle will allow students to review the totality of their daily observations and recordings and to easily recognize the "full circle" of this cycle. Both approaches will support student recognition of the pattern of the lunar cycle.

Once students have finished looking at the lunar cycle, ask them questions like these:

  • Scientists call the changes in the moon "phases." Did you see phases of the moon that look like the ones you have on your calendar?
  • Did you notice that the way the moon looks as it orbits the earth creates a pattern? What pattern do you see?
  • The moon's phases create a pattern. Can you guess how the pattern goes on your Lunar Cycle Calendar (hand out the blank calendar)?

The Moon Phases student esheet challenges students to consider the pattern the moon creates as it makes a full orbit around the earth. When they are ready to complete their Lunar Cycle Calendar, provide them with the cut out pieces from the Main Phases of the Lunar Cycle.

Once students have successfully sequenced the main phases, you could have them work on putting the lunar cycle in order using another blank calendar and cut out pieces from the Lunar Cycle Calendar.

After students have completed these two activities, as them questions like these:

  • Point to the full moon on your Lunar Cycle Calendar. How many days are there between the full moon and the next main phase?
  • What does the moon look like on the sixth day of the cycle? How about on the twelfth day? On the eighteenth day?
  • Do you see a pattern being created by the phases of the moon? Can you describe that pattern?


To help assess students' comprehension of the concepts covered in this lesson, ask them to take the "Lunar Cycle Challenge!" (Make sure students understand that lunar refers to the moon.) Students should use their Moon Phases student esheet to go to the Lunar Cycle Challenge, which is an online activity where students are challenged to drag various images of the moon to their correct places in the lunar cycle. Once again, reading students can utilize the esheet on their own, while you can help learning to read students access this website. Once on the website, there is an auditory guide to explain how to use the interactive.

As a closing, reflective activity, lead a group discussion about what students have learned from this lesson. Ask questions that will encourage them to share what they learned, what they are interested in learning more about, and questions that will help you assess their comprehension of the benchmarks of this lesson.

  • What pattern do the phases of the moon create?
  • Do you think that this pattern helps us know what the moon will look like tomorrow night?
  • Can you think of other places in nature where you see patterns?
  • How long did it take for the moon to go through one cycle (look the same again)?
  • The next time you are a Moon Observer, what would you like to look for?


Keeping in mind the benchmarks of this lesson, look for ways to help students build upon their current understanding of the patterns we find in nature as well as the lunar cycle. Remember that encouraging science literacy in young students includes areas we might not traditionally consider. Students can explore and communicate their scientific investigations through music, storytelling, writing, drawing, sculpting, and building as well as the more traditional ways of conducting experiments, creating hypotheses, and recording observations. Inquiry based science is most meaningful if it begins with the student's curiosity and world of reference and then branches out into unfamiliar, exciting territory. Refer to these websites to spark that curiosity!

Also, try the book, The Moon Seems to Change by Franklyn Branley. If you have access to this book, you might want to read it in the first part of this lesson.

If any students in the class have a telescope or binoculars, they could observe the moon with one of these and report back to the class what they saw.

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Lesson Details

Grades Themes Type Project 2061 Benchmarks National Science Standards