Moon Phases and Models

Article excerpt

From the time they are very young, children are naturally curious about the Moon. They may wonder about the different shapes of the Moon when they look up at the night sky. In this month's primary lesson, students discover through direct observations and reading that the Moon's shape follows a pattern. In the upper-elementary lesson, students explore the reason for this pattern using a model.

This Month's Trade Books

Phases of the Moon

By Gillia M. Olson.

Capstone Press. 2007.

ISBN 0736896171.


Grades K-4

Simple text and photographs introduce Moon phases, including why they occur and what they are called.

The Moon Book

By Gail Gibbons.

Holiday House. 1997.

ISBN 0823413640.

Grades K-4


The Moon Book identifies the Moon as our only natural satellite, describes its movement and phases, and discusses how we have observed and explored it over the years.

Curricular Connections

According to the National Science Education Standards, the focus of space science in the early years should be on the idea that objects in the sky have observable patterns of movement. By observing the day and night sky regularly, early elementary students can learn to identify sequences of changes and look for patterns in these changes. Specifically, when it comes to the Moon's phases, students should notice that "the observable shape of the Moon changes from day to day in a cycle that lasts about a month" (NRC 1996, p. 134). This month's lesson for grades K-3 students is limited to making observations, developing descriptions, and finding patterns; whereas grades 4-6 students use a model to explore the concept that Moon phases are caused by the Moon's orbit around Earth.


For Grades K-3: Moon Monitors

Engage: Show students the photographs of the Moon from Phases of the Moon without reading the text. Ask them what they notice or wonder about the Moon. Prepare a large OWL (Observations/Wonderings/Learnings) chart and keep it posted prominently in the classroom for the duration of the unit. First model your own wonderings about the Moon by writing the following questions on the OWL chart under the "W" (Wonderings) section: Does the Moon really change shape? Where does the Moon's light come from? Does the Moon's shape follow a pattern? How long does it take for the Moon to go through its changes? Then, invite students to write their own questions about the Moon on large sticky notes to post in the wonderings section of the OWL chart.

Explore: Ask students how they might find the answers to some of their questions. Discuss that scientists find answers by making careful observations, doing experiments over and over, communicating with other scientists, etc. Tell students that they can find out more about the Moon by observing it every evening for a month. Give each student a copy of "My Moon Journal" (see NSTA Connection). Ask them to look at the Moon each night and draw what it looks like (if it can be seen). In the classroom, keep a daily bulletin board of the Moon phases for a month. Ideally, students should make their own observations of the Moon for at least a month, but Moon calendars can also be downloaded at

Note: A common misconception about the Moon is that the Moon gets larger and smaller. Empty circles on the "Moon Journal" student page are provided so that students can darken the areas of the Moon that are not lighted. This method of recording Moon phases takes into account that the entire Moon is present, even if some of its surface cannot be seen.

Explain: Discuss students' observations throughout the month using some of the following questions: Was the Moon the same shape each time you saw it? (No.) Did you see the Moon every time you looked for it? …