Tell the time using the sun and a shadow!
Early Learning Goal links
Understanding the World ELG: Past and Present – Talk about the lives of the people around them and their roles in society;
Understanding the World ELG: People, Culture and Communities – Describe their immediate environment using knowledge from observation, discussion, stories, non-fiction texts and maps;
Understanding the World ELG: The Natural World – Understand some important processes and changes in the natural world around them, including the seasons and changing states of matter.
Expressive Arts and Design ELG: Creating with Materials
– Safely use and explore a variety of materials, tools and techniques, experimenting with colour, design, texture, form and function;
– Share their creations, explaining the process they have used;
STEM vocabulary to introduce
Light, dark, shadow, source, block, change, shape, travel, long, short, big, small, straight, time, hour, minute, second, day, night.
Before you start
You may want to read a clock book such as Topsy and Tim: Our Day Clock Book to introduce time over a day.
If you are making lots of sun dials, you may want to cut the circles first!
Show the children the lighting technician poster and tell the children that they are going to be lighting technicians for this activity.
Ask the children if they know what a lighting technician does. Lighting technicians design the way lights are used in television programmes, films, concerts, and in the theatre or plan how to light up buildings, statues or bridges from the outside.
Tell the children about the attributes. Lighting technicians are:
Observant and look carefully at light and shadows
Creative in the way they use lights to make people feel happy, sad, frightened or excited
Collaborative when they work in a team to set up lights for shows, filming and events
Tell the children that they are going to be lighting technicians and that they are going to be observant. They are going to be observing the way the sun moves and the way shadows change across a day. They are going to be creative and use this to make a sun dial which they will be able to use to tell the time on sunny days. You might want to explain that this is the way people told the time before watches and clocks. The children may need to be collaborative if you are making one sundial for the class.
How to make a sun dial
Draw around the plate and cut out a circle. Stick a lump of sticky tack to the centre of the underside. Stick your pencil through the centre of the circle into your sticky tack.
Put your sundial in the sun. On the hour, mark where the shadow of your pencil falls and the time. Leave the dial exactly where it is for the day.
Check your sundial every hour and mark the position of the shadow and the time on the face. Point the sundial in the same direction as when you made it to tell the time by observing the shadow.
You could ask
While making the sun dial, you could ask:
- What is the pencil for?
- Why does it need to be sunny?
- Can you describe the shape of the shadow?
- What has happened to the shadow?
- What do you think will happen next?
- Where do you think the shadow will fall next?
- Why is the shadow moving?
When using the sun dials, you could ask:
- What time is it?
- How do you know?
- Why does the shadow move?
- Why is the shadow longer at times and shorter at other times?
- Why do you need to point the sundial in the same direction each time you use it to tell the time?
- What would happen if it was a cloudy day?
Other things to try – observing shadows over a day
Place a few toys somewhere sunny and then use the pencil or chalk to draw the outline of their shadows.
Leave the toys and come back later. Draw around the new shadow.
Do the same thing later in the day and see how the shadows have moved again.
You could ask:
- Have your shadows moved?
- Which way have they moved?
- Have your shadows grown longer or shorter, wider or narrower?
- Is there anything that you noticed about the shadows?
The science of sun dials
We have put together some useful information about the science of sun dials to accompany this activity. Don’t worry, this is for your information only and to help you answer any questions children may have. We don’t expect you to explain this to the children in your setting!
Why did the shadows move?
Shadows form when light is blocked by an opaque (solid) object. For this investigation, the light you are using travels from the Sun and is blocked by the pencil of your sundial. The shadow falls opposite to where the Sun is in the sky. Although the Sun appears to move across the sky, we know it is the Earth that is rotating. This causes the Sun to look like it’s moving. Over a day we see a pattern: the sun rises in the east and in the morning as the Sun is rising, your shadows were long, and point to the west. At 12 noon, the Sun appears at its highest in the sky, the shadows are at their shortest. In the afternoon, the Sun is in the west and the shadows point to the east. The shadows get longer and longer until the Sun sets in the west.
What you’ll need
- Sun – this activity can only be done on a sunny day
- A place in your setting that is in the sun all day
- A clock, watch or phone to tell the time
- A sheet of A4 card per sun dial
- A dinner plate or similar to draw around
- Sticky tack
- A large stick in the grass, sand or soil or a moveable post such as a rounder’s base from the PE cupboard
- Stones as markers on grass or soil
- Chalk to mark on paths, tarmac or concrete.
- The lighting technician poster
- Preparation time to cut circles
- 5 – 10 mins per hour across the day
This activity needs to be done every hour, on the hour, throughout the day.Lighting technician poster