New
New
Lesson 8 of 12
New
New
- Year 3
Shadow size: do
I can measure and record information about shadow size.
Lesson details
Key learning points
- The size of a shadow changes depending on the distance of an object from the light source.
- Height and distance can be measured using a ruler or tape measure.
- The results of an investigation can be recorded in a table.
- A table of results needs headings for each column. This helps other people to understand the information.
Keywords
Shadow - A shadow is a dark shape that is formed when an object blocks a source of light.
Light source - Something that is a light source produces its own light.
Distance - Distance is how far away something is or how far an object has travelled.
Measure - To measure is to use equipment to find numbers to describe a feature of something such as its length, weight, size or time.
Table - A table is a grid in which information can be recorded and stored.
Common misconception
The size of a shadow does not change.
Explanation of how the size of shadows change depending on the distance of the object from the light source.
This lesson follows on from Shadow size: plan. Pupils can use their own plans or Izzy and Jacob's ideas to investigate how the distance between an object and a light source affects the size of a shadow. Working in front of a wall will make it easier for pupils to measure shadows accurately.
Teacher tip
Equipment
Torches or lamps, opaque objects, rulers, tape measures.
Content guidance
- Exploration of objects
Supervision
Adult supervision recommended
Licence
This content is © Oak National Academy Limited (2026), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
Lesson video
Loading...
Prior knowledge starter quiz
6 Questions
Q1.Shadows are formed when ...
Shadows are formed when ...
light passes through an object.
there is no light.
Q2.Which of these is not a light source?
Which of these is not a light source?
a torch
a lamp
Q3.True or false? The size of a shadow changes depending on the size of the light source.
True or false? The size of a shadow changes depending on the size of the light source.
Q4.The distance between an object and a light source changes ...
The distance between an object and a light source changes ...
the colour of a shadow.
the shape of a shadow.
Q5.How can scientists find the answers to questions?
How can scientists find the answers to questions?
by asking questions
by sorting objects into groups
Q6.What do we call an investigation where only one thing is changed to find its effect on another thing that is measured, and all other things are kept the same?
What do we call an investigation where only one thing is changed to find its effect on another thing that is measured, and all other things are kept the same?
grouping
researching
Assessment exit quiz
6 Questions
Q1.Which kind of material produces the darkest shadows?
Which kind of material produces the darkest shadows?
The darkest shadows are formed when a translucent object blocks the light.
The darkest shadows are formed when a transparent object blocks the light.
Q2.Which statement is true?
Which statement is true?
Shadows do not change size.
Shadows change size if the light source is changed.
Q3.Which of these can be used to measure the size of a shadow?
Which of these can be used to measure the size of a shadow?
a stopwatch
a measuring jug
Q4.What is distance?
What is distance?
How heavy something is.
How bright something is.
Q5.What do scientists use to record the results of an investigation?
What do scientists use to record the results of an investigation?
a plan
a chair
Q6.Why do scientists put a heading at the top of each column in a table?
Why do scientists put a heading at the top of each column in a table?
to practice spelling useful words
to make the table look good
