How to Tell Time from the Sun - Sundial

While you probably have the knowledge that when the sun is close to setting, it’s pretty late, and when the sun has just risen, it’s pretty early, but did you know that it is possible to actually tell the time by the sun? A sundial will help you to know the time depending on the position of the sun. This is how people thousands of years ago were able to tell the time without the use of clocks! With this experiment, you’ll make a sundial and look at it over the year to see how it will change.
Question
What makes the position of the sundial change as the year goes on? How to tell time from the sun lesson for kids
Materials

Pencil
Permanent market
Hammer
Nail
Plastic straw
A wooden board, at least 12 in. square
A long and sunny day in the summer to start on
Tacks
Ruler
A watch

Procedure

Take the hammer, nail, and board. Hammer the nail about a ¼ of an inch into the middle of the board.
Cut the straw into a length of 6 in.
Put the piece of straw over the nail.
When the sun comes up, find an area that has plenty of sun and is flat. Put the board here. Be certain that no shadows are going to block the sun from getting to your sundial.
Look at the shadow the end of the nail makes. When it is the top of the hour, mark the end of the shadow and place a tack there.
Where the tack is, write down what hour this represents.
Leave the sundial alone and make sure it won’t be moved!
Once an hour has gone by, go out and place another tack and write the time.
Continue marking the time until the sun goes down.
If you are happy with your marks and are sure the sundial was not moved, write the times with permanent marker.
Keep an eye on your sundial and think about when you wouldn’t be able to use it.
Keep checking on your sundial through the year.

Results
You may get different results depending on the area you live. Typically, the shadow the nail makes will make a semi-circle around the board from when the sun comes up to when it goes down. At the beginning and end of the day, the shadow will be longer and it will be shorter in the middle of the day, when the sun is the highest. The shadow will get longer towards December, but the sun might go down before you can even see some of the time you saw in the summer. You’ll see all the times again once spring comes back around! - For teaching students in 4th, 5th and 6th grades on how to tell the time from the sun.