Exploring Light Properties

Overview

This is a 60-minute lesson designed for 24 students, split into groups of 6, focusing on a practical and engaging exploration of light. It directly aligns with the National Curriculum for England’s Science programme of study for Key Stage 2 (Years 5 and 6), specifically referring to the unit on Light.

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National Curriculum References

• Subject: Science
• Programme of Study: Key Stage 2 (Years 5 and 6)
• Topic: Light
• Learning Objectives:
  • Recognise that light appears to travel in straight lines.
  • Use the idea that light travels in straight lines to explain that objects are seen because they give out or reflect light into the eye.
  • Explain that we see things because light travels from light sources to our eyes or from light sources to objects and then to our eyes.
  • Use the idea that light travels in straight lines to explain why shadows have the same shape as the objects that cast them.

Reference: National Curriculum for England, Science Programmes of Study (Key Stage 2: Light)

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Learning Objectives

By the end of this lesson, pupils will be able to:

1. Describe how light travels in straight lines.
2. Explain how shadows are formed and why they have the same shape as the objects casting them.
3. Demonstrate how an object is seen because of light travelling to the eye.
4. Work collaboratively to investigate light and shadows through practical activities.

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Resources Needed

• Torches (one per group)
• Opaque objects of different shapes and sizes (cuboids, spheres, flat shapes)
• White card or paper (to observe shadows)
• Mirrors (small handheld)
• Prisms or CD discs (to demonstrate light refraction and dispersion)
• A darkened part of the classroom or black-out blinds
• Science notebooks and pencils
• Rulers or metre sticks
• Large plain wall or screen surface for shadows
• Sticky tack or Blu Tack to fix objects in place

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Lesson Structure

Starter (10 minutes)

Engage and Activate Prior Knowledge

• Begin with a quick discussion: “What is light? Where does it come from?”
• Encourage pupils to share experiences with torches, sunlight, or shadows.
• Show a short, visually engaging demonstration using a torch in a darkened corner to reveal how light travels straight by casting a narrow, straight beam on the wall.
• Ask: “Why do you think you can see the beam in the air sometimes?” (Particles in the air reflecting light)

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Main Activity (40 minutes)

Part 1: Investigating Shadows (20 minutes)

• Pupils work in groups of 6. Each group will:

  1. Use torches to shine light on opaque objects fixed on a white surface.
  2. Observe and sketch shadows produced.
  3. Measure how the shadow size changes when moving the object closer to or further from the light source.
  4. Record observations about shape, size, and sharpness of shadows in notebooks.

• Emphasise inquiry-based learning: “Predict what will happen if we move the object closer to the light. Test your idea.”

• Teacher circulates to prompt discussion:

  • “Why do shadows have the same shape as the objects?”
  • “What happens to the shadow when you move the light source?”
  • “How can we explain this using straight lines of light?”

Part 2: Exploring Why We See Objects (20 minutes)

• Each group uses torches and mirrors to observe reflections.
• Task: Direct the torchbeam at a mirror to see how light changes direction but travels in straight lines before and after.
• Introduce a prism or CD to demonstrate white light splitting into colours and spark curiosity about how light behaves.
• Pupils discuss and write short explanations in their science books on:
  • How the light path changes with mirror reflection.
  • Why objects are visible only when light reaches our eyes either directly or by reflection.
• Finish with an innovative challenge: Groups use mirrors and torches to “send” light beams to a target placed around obstacles, demonstrating reflection and straight-line travel in a problem-solving context.

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Plenary (10 minutes)

• Reflective whole-class discussion. Ask:
  • “What did you learn about light today?”
  • “How can our observations explain how shadows form?”
  • “Why do we see objects?”
• Pupils share their drawings and explanations.
• Summarise key points, explicitly linking back to the National Curriculum objectives.
• Quick quiz or thumbs up/down to assess understanding of key concepts (straight-line travel, shadows, reflection).

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Assessment and Differentiation

• Formative assessment:
  Observations of group discussions, pupil questioning, and notebook entries during activities.
• Summative assessment:
  Science notebooks reviewed for accuracy in explanations and quality of diagrams.
• Support for SEND pupils:
  Provide pre-drawn shadow outlines to annotate, simplified language prompts, and additional adult support in groups.
• Challenge for more able pupils:
  Encourage prediction of shadow length using simple proportion concepts or investigate light refraction angles with prisms.

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Cross-Curricular Links

• Maths: Measuring distances and sizes of shadows; recording data.
• Art: Drawing shadows and light reflections accurately.
• PSHE: Collaborative teamwork and communication skills.

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Extension Ideas

• Use coloured filters to investigate how coloured light affects shadow colour.
• Explore how light behaves with transparent and translucent objects for more advanced understanding.

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By encouraging active discovery, critical thinking, and practical collaboration, this lesson ignites curiosity about light in a way that is memorable and fully aligned to the UK National Curriculum, making science both tangible and exciting for Year 5 and 6 pupils.