• The lesson offers pupils an introduction into how we see and activities demonstrating that light travels in straight lines from objects to our eyes.
  • It introduces the idea of ‘light rays’ and how to represent how light travels with light ray diagrams.
  • The main Scientific Method focus of the lesson is to develop scientific skills of shaping a hypothesis/make a prediction and a method to test the hypothesis.
All children should be made aware of and confidently follow the core rules of conduct in a science lesson:
  • Wash hands regularly.
  • Put nothing in their mouths or eyes.
  • Follow all instructions given by adults.

Specific to this lesson:

  1. Never stare directly at the sun or very bright objects, always use protective eyewear.
  2. Please, read health and safety requirements for specific procedures and equipment
  1. Light needs a medium to travel through. • Light can travel in a vacuum.
  2. The more luminous the space the further light travels. • Light travels at a fixed speed until it is either reflected or absorbed by a material it strikes.
  3. Objects that look shiny are sources of light (e.g., the Moon). • All objects are either classified as luminous or non-luminous.
  4. Light from some sources is hot (e.g., from the Sun or bright bulb) and light from the other sources is not. • Red wavelengths transfer less energy than Violet light.

Review all the stages to a scientific plan including:

  • Identifying Independent and Dependent Variables
  • Shaping a question, they can test
  • Making a Prediction / Hypothesis
  • Justifying their hypothesis
  • Method (plus research)
  • List of Equipment
  • Risk Assessment

Electromagnetic (EM) radiation - form of energy that is all around us and takes many forms, such as visible light, radio waves, microwaves, X-rays and gamma rays
Light (visible light) - electromagnetic radiation within the portion of the electromagnetic spectrum that can be perceived by the human eye
Luminous objects – objects that are sources of its own light
Non-luminous objects – not sources of light, but can reflect light from other objects
Reflectors – non-luminous objects
Emit – we say that when a luminous object produces light, it emits light
Dull - an object that is dull is a poor reflector

Learning Outcomes - 1 min

Challenge Scientific SKills Knowledge

Level 1

• Develop the skill of conducting simple preliminary experiments to help shape questions for further research.
• Practise the skill of applying the terms “independent” and “dependent” variables.
• Practise the skill of making a prediction.

• Learn that light comes from Luminous objects.
• Learn that light is reflected off non-luminous objects.

Level 2

• Specifically identify independent and dependent variables.
• Practise the skill controlling variables to test and measure in an experiment.
• Develop the skill of starting to plan an investigation and make predictions.

• Explain that all luminous objects emit different amounts of light.
• Explain that light is part of a ‘spectrum’ - The Electromagnetic Spectrum.
• Learn that white light consists of 7 main colours.

Level 3

• Practise the skill of controlling variables in their own investigations.
• Design their own experiment to test their own question and potentially record their own observations independently.

• Explain where most of the light we use comes from - ultimately the sun!

Riddle #1

It can fill a room without occupying space - what is it?



Riddle #2

A man was driving a black truck. His lights were not on. The moon was not out. A lady was crossing the street. How did the man see her?


It was a bright sunny day!

Step-by-step demonstration for plasma sphere
  1. Switch it on.
  2. Explain that this is a Plasma Sphere.
  3. Explain that the little flickering bands of light are plasma (the 4th state of matter) and that this is what the Sun is made from and where we ultimately get most of our light.
  4. Allow the pupils to touch the sphere and see the plasma tendrils discharge a little of their energy through the contact made. Bring the fluorescent tube near the plasma sphere. Before they touch, the tube should light!
Suggestions for discussion: Use this demonstration to discuss the Sun and how it emits most of the light we use and see on Earth (you may have to explain the step-by-step process of):
  • Sunlight
  • Trapped by plants
  • Plants buried and turned to coal
  • Coal burnt in power stations
  • Power stations create electricity
  • Electricity used in light bulbs to create light!
Science explanation
The ball is filled with gas, typically neon, at low pressure. In the centre of the sphere is a high alternating voltage. Applied to the gas this voltage causes appearance of discharge – alongside with neutral gas particles there’s a significant amount of freely moving charged particles (ions and electrons). When touching the ball, you create a path for electrons to the Earth and attract arcs to the point where you touch the ball. Thanks to the high alternating voltage in the centre and fast-moving charged particles inside, the plasma ball works as a source of electromagnetic waves, the arcs of plasma act as antennae. The created electromagnetic field is strong enough even beyond the walls of the plasma ball. Bringing the fluorescent tube near to the plasma ball allows the electrons inside to be accelerated by this field, and those moving electrons constitute an electric current, which causes the bulb to light up.

Step-by-step demonstration

  1. Hand out the Spectrum Cards and ask pupils to stick it to their books.
  2. Explain that the topic light is a part of much bigger chapter of the science – electromagnetic radiation. Though having some differences in the behaviour different parts of the electromagnetic spectrum have similarities.
  3. Explain that light is a form of visible energy that is emitted from atoms.
  4. White light consists of 7 colours that we call the ‘spectrum’ and we can see it when white light passes through objects that split them up.
  5. Tell pupils that during the term they are going to refer to this picture when discovering new features of light.

Suggestions for discussion

  1. Before handing out the cards ask pupils if they have ever:
    • listened to the radio
    • warmed up their food in a microwave
    • felt warmth from a heater and used remote controls
    • heard about UV light
    • had an x-ray scan
    • heard of nuclear radiation
  2. Ask if they know what all the above have in common (be prepared for a blank look.)
  3. Tell them that all of the mentioned things alongside light are examples of electromagnetic radiation.
Science explanation
The electromagnetic spectrum is the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies.
Visible light is the part of the EM spectrum the human eye is the most sensitive to. Visible light is typically absorbed and emitted by electrons in molecules and atoms that move from one energy level to another.

Step-by-step demonstration

Show the pupils the sunglasses and explain why it is important never to look at the Sun (or other very bright light) directly and always use sunglasses when doing so. 

Suggestions for discussion

  1. Not all the light sources are the same, they differ in brightness.
  2. Ask for examples of bright and dim light sources.
Science explanation
Staring at bright light makes the retina's light-sensing cells become overstimulated. When it happens, these cells release massive amounts of signalling chemicals, injuring the back of the eye. The Sun is not just a bright source of light it also emits UV light, which causes additional damage to your retina cells. Good quality sunglasses reflect some visual light making it dimmer and nearly all UV light saving your eyes from damage.

Pupils will need access to:

Video: https://bit.ly/3a4Lke0

Step-by-step demonstration

  1. Explain that when light hits a dull object, it reflects only a small amount of light, all the other light is caught (absorbed) by the object. The less light is reflected the worse we see details of the object.
  2. Tell pupils that black paint reflects not that much light and it is the reason why often black objects look dull (if they are not coated with a shiny layer above the paint.)
  3. Show the first part of the video where a 3D head painted with one of the blackest paints in the world looks nearly like a shadow and we can’t see much face details.
  4. Continue with the video and explain that even though the paint doesn’t let the object to reflect the light, if we take a light source bright enough (the brightest flashlight in the world) we will be able to see details of the object again.


Suggestions for discussion

  1. There are no real objects that reflect all the light or absorb all the light. There is always part of the light absorbed and part of the light reflected.
  2. What happens to an object when it absorbs light?

Science explanation

When light strikes the object part of it is absorbed and part is reflected. Black absorbs all the colours from the visible spectrum. If the object absorbs nearly all the light there is not enough reflected light for our eyes (and brain) to see the details of the object clearly.



Pupils will need access to:

  • candle
  • torch
  • small mirror
  • coin
  • pen
  • picture of the moon
  • picture of the sun
  • picture of the Earth
  • piece of wood

Step-by-step instructions

  1. Set up the circus of luminous and non-luminous objects.
  2. Hand out observation sheet and explain how to fill it out (record which object is luminous and which is not and give a short explanation why they think so.)

Suggestions for discussion:

  • Luminous and non-luminous objects – sources of lights and reflectors of light.
  • Do different luminous objects emit the same light? In what aspects are they different? (brightness, colour)
  • Are there 2 categories they could place the luminous objects in? (Looking for natural vs man-made.)
  • Why non-luminous objects are colourful? (Tricky introduction question for future colour question.)
All the objects we can see can be divided into two groups.
We call objects that make (emit) light luminous, and those that don’t – non-luminous.
Darkness is the absence of light and we can’t see when there’s no light.
We see non-luminous objects only in the presence of the light source.
When light from a luminous object hits a non-luminous object, it reflects to our eyes. That’s why we call non-luminous objects reflectors.
Ask the children to identify luminous objects in the sky in the daytime.
Ask about the night sky. Explain that even though the Moon seems to shine it actually is not a source of light as it reflects light from the Sun, but the stars are light sources.

New vocabulary
Recording and discussing findings using simple scientific language, drawings, labelled diagrams, keys, bar charts, and tables
reporting on findings from enquiries, including oral and written explanations, displays or presentations of results and conclusions
Gathering, recording, classifying and presenting data in a variety of ways to help in answering questions
As an additional piece of contextual information about light it’s good to mention that ‘Plants’ need light to grow, some types of plants require highly luminous or shady areas to grow.
Children could investigate and write about light sources in the periods of history children are studying or others. They could even create a ‘Sources of light’ timeline.
In their artwork children could use materials with different capacity to reflect light and shine a light beam on it from different places.
Using reflectors for road safety.