Science · Year 5 · Earth and Space · Spring Term

Day and Night

Using the Earth's rotation to explain the cycle of day and night and the apparent movement of the sun.

• National Curriculum Attainment Targets
• NC-KS2-Science-Y5-ES-2

About This Topic

The Phases of the Moon explores why the Moon's appearance changes in a predictable cycle throughout the month. Students learn that the Moon does not produce its own light but reflects the light of the Sun, and its 'phases' are determined by its position relative to the Earth and the Sun. This topic is part of the KS2 Earth and Space curriculum, requiring students to describe the movement of the Moon relative to the Earth.

This unit is important for understanding celestial cycles and the relationship between the Moon and Earthly phenomena like tides. It encourages students to become regular observers of the night sky. This topic comes alive when students can physically model the Moon's orbit using spheres and light sources to see how shadows create the different phases we see from Earth.

Key Questions

1. Explain why the sun appears to move across the sky when it is actually the Earth moving.
2. Analyze how shadows help us determine the time of day.
3. Predict what would happen to day and night if the Earth stopped rotating.

Learning Objectives

• Explain the Earth's rotation as the cause of the day and night cycle.
• Analyze how the apparent movement of the sun across the sky is due to Earth's rotation.
• Compare the length of daylight and darkness in different seasons based on Earth's tilt and rotation.
• Predict the consequences for day and night if the Earth's rotation were to cease.

Before You Start

Light and Shadows

Why: Students need to understand how light travels and how opaque objects block light to grasp how shadows are formed and change.

Basic Understanding of the Solar System

Why: Prior knowledge that the Earth is a planet orbiting the Sun is foundational for understanding Earth's rotation in relation to the Sun.

Key Vocabulary

Rotation	The spinning of the Earth on its axis, which takes approximately 24 hours to complete, causing day and night.
Axis	An imaginary line passing through the North and South Poles around which the Earth spins.
Apparent Movement	How an object appears to move from a particular viewpoint, even though it is stationary or moving differently. The sun appears to move because the Earth is rotating.
Daylight	The period of time when the sun is visible above the horizon, providing light.
Night	The period of time when the sun is below the horizon, and the sky is dark.

Watch Out for These Misconceptions

Common Misconception

The Moon changes shape because of the Earth's shadow.

What to Teach Instead

Students often confuse moon phases with lunar eclipses. By using the 'Moon Phase Circle' simulation, students can see that the phases are caused by our view of the Moon's own shadowed side, not by the Earth getting in the way of the Sun's light.

Common Misconception

The Moon only comes out at night.

What to Teach Instead

Many children believe the Moon 'replaces' the Sun. Encouraging daytime moon spotting and discussing why it's sometimes visible during the day helps students understand that the Moon is always orbiting Earth, regardless of whether the Sun is up or not.

Active Learning Ideas

Simulation Game: The Moon Phase Circle

In a dark room with a single bright light (the Sun), students hold a white ball (the Moon) at arm's length. As they slowly turn their bodies (the Earth) in a circle, they observe how the light hits the ball at different angles, creating the crescent, half, and full moon shapes.

40 min·Individual

Inquiry Circle: Moon Diary Analysis

After keeping a moon diary for a month, students work in small groups to compare their sketches. They look for patterns in the data, identify the names of the phases (e.g., waxing gibbous, waning crescent), and use their findings to predict what the moon will look like in one week's time.

50 min·Small Groups

Gallery Walk: Moon Myths vs. Science

Display various historical myths about the moon alongside scientific facts. Students rotate in pairs, discussing how ancient people explained the moon's changes and how our modern scientific understanding of orbits and reflection provides a different explanation for the same observations.

30 min·Pairs

Real-World Connections

• Astronomers and astrophysicists use their understanding of Earth's rotation to calibrate telescopes and predict celestial events, ensuring accurate observations of stars and planets.
• Navigation systems, from ancient mariners using the sun's position to modern GPS, rely on precise knowledge of Earth's rotation and its effect on time and location.
• Farmers and gardeners plan planting and harvesting schedules based on seasonal changes in day length, which are a direct result of Earth's tilt and rotation.

Assessment Ideas

Quick Check

Ask students to hold a globe and a flashlight. Instruct them to model Earth's rotation and explain to a partner why one side of the globe is lit (day) while the other is dark (night). Ask: 'What happens to the light on your side as you spin the globe away from the light?'

Exit Ticket

Provide students with a scenario: 'Imagine the Earth stopped spinning but still orbited the Sun.' Ask them to write two sentences predicting what would happen to the cycle of day and night. Collect and review for understanding of rotation's role.

Discussion Prompt

Pose the question: 'Why does the sun seem to rise in the east and set in the west?' Facilitate a class discussion where students use the terms 'rotation' and 'axis' to explain the apparent movement of the sun. Prompt them to explain how this is different from the sun actually moving.

Frequently Asked Questions

Why does the Moon appear to change shape?

The Moon doesn't actually change shape; it's a solid sphere. We only see the part of the Moon that is being lit up by the Sun. As the Moon orbits the Earth, we see different amounts of its lit-up side. These different views are what we call the 'phases' of the Moon.

What are the main phases of the Moon?

The cycle starts with the New Moon (not visible), followed by Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, and Waning Crescent. 'Waxing' means the visible part is growing, while 'waning' means it is shrinking.

How can active learning help students understand Moon phases?

Moon phases are a matter of perspective. Active learning strategies, like the 'ball and torch' simulation, allow students to literally see the perspective change for themselves. By being the 'Earth' in the center of the model, they can observe how the light and shadow shift, making the transition from a 2D diagram to a 3D reality much easier.

How long does it take for the Moon to orbit the Earth?

It takes about 27.3 days for the Moon to complete one orbit around the Earth. However, because the Earth is also moving around the Sun, the cycle from one New Moon to the next takes about 29.5 days. This is where our concept of a 'month' originally came from.

From the Blog

25+ Social Emotional Learning Activities for Every Classroom: A CASEL-Aligned Guide

Discover 25+ evidence-backed social emotional learning activities aligned to CASEL's 5 competencies, for inclusive classrooms and teacher wellbeing.