Science · Year 2 · The Changing Sky · Term 3

Shadow Play

Students will investigate how the sun's position affects the length and direction of shadows throughout the day.

• ACARA Content Descriptions
• AC9S1U02

About This Topic

Shadow play examines how the sun's position in the sky influences shadow length and direction over a day. Year 2 students observe shadows lengthening in the morning when the sun is low in the east, shortening at midday when overhead, and lengthening again in the afternoon toward the west. They compare shadows from tall and short objects at the same time, discovering proportional lengths, and design simple experiments to track these changes using metre sticks, chalk, and clocks.

This content connects to AC9S1U02 by building skills in recognising patterns, making predictions, and collecting evidence through observation. Students represent data in tables or drawings, which strengthens their understanding of daily sky cycles and lays groundwork for concepts like Earth's rotation.

Active learning suits this topic well. Outdoor shadow hunts or collaborative tracking sessions let students gather real-time data from their schoolyard. Such direct experiences clarify cause-and-effect relationships between sun position and shadows, boost engagement through play, and help students internalise patterns through repetition and peer discussion.

Key Questions

1. Analyze how shadows change length and direction from morning to evening.
2. Compare the shadow of a tall object to a short object at the same time of day.
3. Design an experiment to track shadow changes over several hours.

Learning Objectives

• Compare the length and direction of shadows cast by the same object at different times of the day.
• Analyze how the position of the sun influences the size and orientation of shadows.
• Compare the shadow lengths of objects of different heights at a single point in time.
• Design a simple experiment to record and track shadow changes over several hours.

Before You Start

Light and Sound

Why: Students need a basic understanding of light as a source that can be blocked to form shadows.

Observing and Describing

Why: This topic requires students to observe changes and describe them accurately, skills developed in earlier observational science activities.

Key Vocabulary

shadow	A dark area formed when an object blocks light from a source, like the sun.
sun's position	Where the sun appears in the sky, which changes from morning to afternoon.
length	How long a shadow is, which changes depending on the sun's height.
direction	The way a shadow points, which depends on where the sun is in the sky.

Watch Out for These Misconceptions

Common Misconception

Shadows get shorter because the sun gets hotter.

What to Teach Instead

Shadows shorten as the sun rises higher, changing angle of light rays. Hands-on angle demos with torches and objects reveal this geometry. Group measurements at different times correct the heat idea through evidence comparison.

Common Misconception

Shadows always point east-west.

What to Teach Instead

Shadows point away from the sun, so direction shifts from east to west over the day. Outdoor hunts with compasses or sun clocks show directional changes. Peer sharing of observations builds consensus on patterns.

Common Misconception

Clouds make shadows disappear.

What to Teach Instead

Shadows form whenever sunlight is blocked, regardless of clouds. Paired torch experiments indoors mimic this. Students test on cloudy days, linking back to sun position as the key factor.

Active Learning Ideas

Outdoor Tracking: Stick Shadows

Place identical sticks vertically in the ground at three times: morning, noon, afternoon. Students mark shadow ends with chalk and measure lengths with rulers. Groups discuss patterns and draw time-series diagrams.

45 min·Small Groups

Pairs Compare: Tall vs Short

Provide pairs with a tall cone and short block. At the same time each hour, trace shadows on paper. Pairs measure and compare lengths, noting ratios stay similar despite height differences.

30 min·Pairs

Whole Class: Shadow Clock

As a class, position a stick in a sunny spot to create a shadow clock. Mark positions hourly and label times. Predict next shadow position based on prior data.

60 min·Whole Class

Individual Design: Shadow Experiment

Students plan their own test, such as tracking a toy car's shadow. They list materials, steps, and predictions, then test over recess and record results in journals.

25 min·Individual

Real-World Connections

• Architects and urban planners consider how buildings cast shadows to ensure sunlight reaches public spaces and homes throughout the day.
• Farmers use sundials and knowledge of the sun's path to plan planting and harvesting schedules, ensuring crops receive optimal light.
• Navigators historically used shadows cast by the sun and stars to determine direction and time, a practice still relevant in some outdoor survival skills.

Assessment Ideas

Quick Check

Ask students to draw a picture of their shadow at the start of the lesson and again at the end. Have them label: 'Morning Shadow' and 'Afternoon Shadow' and write one sentence comparing their lengths.

Discussion Prompt

Present students with two objects, one tall and one short. Ask: 'If we measure their shadows right now, what do you predict will happen to the shadow of the tall object compared to the short object? Why?' Record student predictions.

Exit Ticket

Give students a worksheet with a drawing of the sun in the east, west, and overhead. Ask them to draw the shadow for each position of the sun, indicating its direction and relative length (short or long).

Frequently Asked Questions

How do shadows change over a day in Year 2 science?

Shadows lengthen when the sun is low in morning or evening skies and shorten when overhead at noon. Direction shifts from pointing east in morning to west in afternoon. Students track this with sticks and chalk outdoors, aligning with AC9S1U02 patterns in natural events.

What activities teach shadow length and direction?

Use stick shadows traced hourly, compare tall and short objects simultaneously, or build shadow clocks. These 30-60 minute sessions in small groups or pairs collect data for pattern spotting. Extensions include prediction challenges to reinforce fair testing.

How can active learning help students understand shadows?

Active approaches like schoolyard shadow hunts and collaborative measuring give direct evidence of sun position effects. Students mark, measure, and discuss in real time, making abstract sky movements visible. This builds ownership of data, corrects misconceptions through peer debate, and links observations to models in 40-60 minute sessions.

Common Year 2 misconceptions about shadows?

Students may think shadows shorten from sun heat or point fixed directions. Corrections come via torch simulations and timed outdoor data. Structured talks help revise ideas, with drawings showing angle changes over time.