Science · Year 1 · Light and Shadows · Summer Term

Changing Shadows

Observing how shadows change throughout the day and with different light sources.

• National Curriculum Attainment Targets
• KS1: Science - Light

About This Topic

The Changing Shadows topic helps Year 1 pupils understand that shadows form when light from a source, such as the sun or a torch, is blocked by an opaque object. Pupils observe how shadows change in length and position throughout the day, noting that shadows are longest in the morning and evening when the sun is low, and shortest at midday. They also investigate how shadows vary with different light sources by experimenting with torches at various distances from objects, predicting and observing larger, sharper shadows when the light is close.

This content aligns with KS1 Science standards on light, fostering key skills like careful observation, simple prediction, and basic explanation. Pupils compare morning and afternoon shadows, connect daily changes to the sun's apparent movement across the sky, and develop an awareness of patterns in natural phenomena. These experiences lay groundwork for later topics on light properties and forces.

Active learning suits this topic well. Pupils gain immediate feedback from outdoor tracking or torch experiments, which makes abstract ideas concrete. Hands-on trials encourage prediction and adjustment, boosting confidence and retention through direct sensory engagement.

Key Questions

1. Compare how a shadow changes from morning to afternoon.
2. Predict how a shadow would look if the light source was very close to an object.
3. Explain why our shadows are longest in the morning and evening.

Learning Objectives

• Compare the length and position of an object's shadow at different times of the day.
• Predict the appearance of a shadow when the light source is moved closer to or further from an object.
• Explain why shadows appear longer in the morning and evening compared to midday.
• Identify the object blocking light to create a shadow.

Before You Start

Properties of Light

Why: Students need a basic understanding that light travels and can be blocked to comprehend shadow formation.

Observing and Describing

Why: This topic requires students to carefully observe changes in shadows and describe their findings accurately.

Key Vocabulary

shadow	A dark area formed when an opaque object blocks light from a light source.
light source	Anything that produces light, such as the sun or a torch.
opaque	An object that does not allow light to pass through it, creating a shadow.
position	The place where something is, referring to where a shadow appears in relation to an object and the light source.

Watch Out for These Misconceptions

Common Misconception

Shadows are always the same size as the object.

What to Teach Instead

Shadow size depends on light source distance; closer lights make bigger shadows. Group experiments with torches let pupils test predictions directly, revising ideas through shared observations and drawings.

Common Misconception

Shadows move by themselves.

What to Teach Instead

Shadows change position because the light source or object moves relative to each other. Outdoor whole-class tracking reveals this pattern over time, prompting discussions that clarify cause and effect.

Common Misconception

Shadows are shortest at sunrise.

What to Teach Instead

Shadows lengthen when the sun is low on the horizon. Repeated morning observations in pairs help pupils notice and explain this reliably through consistent data collection.

Active Learning Ideas

Outdoor Tracking: Daily Shadow Hunt

Take pupils outside in the morning to mark their shadows with chalk around their feet and note direction. Return in the afternoon to compare length, position, and direction. Discuss patterns as a class.

30 min·Whole Class

Small Groups: Torch Distance Play

Provide each group with a torch, teddy bear, and wall. Pupils predict shadow size, then test by moving the torch closer and farther. Record changes on simple charts.

25 min·Small Groups

Pairs: Prediction Stations

Set up stations with objects and lamps at fixed distances. Pairs predict shadow appearance, draw it, then observe and compare. Rotate stations.

35 min·Pairs

Individual: Shadow Journal

Pupils use a sunny spot to draw their shadow hourly over a lesson. Note changes in length and position in a personal journal with labelled sketches.

40 min·Individual

Real-World Connections

• Architects and urban planners consider how buildings cast shadows on public spaces and neighboring structures to ensure adequate sunlight and prevent overshadowing.
• Photographers use light sources, like the sun or studio lights, at different angles and distances to control the size and sharpness of shadows in their images, creating specific moods or highlighting features.
• Farmers use sundials or observe the length of crop shadows to estimate the time of day for tasks like watering or harvesting, especially in areas without clocks.

Assessment Ideas

Exit Ticket

Give each student a drawing of a simple object and a sun in the morning position. Ask them to draw the object's shadow. Then, ask them to write one sentence explaining why the shadow is long.

Discussion Prompt

Hold up a torch and an object. Ask students: 'What will happen to the shadow if I move the torch closer to the object? What will happen if I move it further away?' Encourage them to use the terms 'shadow', 'light source', and 'opaque' in their explanations.

Quick Check

During an outdoor observation, ask students to point to their shadow and describe its position. Then, ask them to compare it to their shadow earlier in the day, using comparative words like 'longer' or 'shorter'.

Frequently Asked Questions

How do shadows change throughout the day in Year 1 science?

Shadows grow longer and shift position from morning to afternoon as the sun appears to move across the sky. Year 1 pupils track their own shadows outside, comparing morning lengths to midday shortness. This builds observation skills and links to the key question on morning and evening shadows.

What hands-on activities teach changing shadows?

Outdoor shadow marking and torch experiments work best. Pupils mark shadows with chalk twice daily, then use torches on objects to see size changes with distance. These build prediction skills through trial and immediate results, fitting KS1 light standards perfectly.

How can active learning help pupils understand changing shadows?

Active learning shines here with real-time experiments like torch play or playground tracking. Pupils predict outcomes, test them, and adjust ideas based on evidence, which strengthens memory and confidence. Group rotations ensure all participate, revealing patterns through collaboration that lectures miss.

Why are shadows longest in the morning and evening?

Low sun angles create long shadows by casting light at a slant across surfaces. Pupils explain this after observing daily changes and torch simulations. Simple models with sticks and lights reinforce the concept, connecting observation to everyday weather patterns.