Summer Science Fun: Simple Sundial

GeekMom Summer Science Fun
Photo: Kelly Knox
Photo: Kelly Knox

Long, lazy summer days call for laid back science experiments! Whether you’re watching ice melt or keeping an eye on a leaf, there are plenty of entertaining experiments that don’t call for Bunsen burners or big explosions. Making a sundial over the course of a day or two is a fun way to take advantage of all that summer sunshine.

All you need are a stick, colorful stones (or stones marked with hours), a notepad, a pencil, and a sunny day.

Start by setting your little scientist on a hunt for a thick, long stick that will form a shadow that’s easy to see in the grass. Push the stick into the dirt in a spot that should get sunshine all day long.

Note where the shadow falls on the grass and place a marker stone on that spot. We used my daughter’s polished rock collection (along with a shell), gathered from various science centers and zoos we’ve visited. We picked a different color for each stone. You can also paint stones with the time marked, or ask your child to select other kinds of markers.

Next, we noted the time each marker would be placed (or was placed).

Photo: Kelly Knox
Photo: Kelly Knox

Run out into the yard every hour to mark the shadow until your sundial is complete.

Photo: Kelly Knox
Photo: Kelly Knox

Use this experiment to talk about the Earth’s rotation and why the shadow appears longer and shorter at different times of the day.

Liked it? Take a second to support GeekMom and GeekDad on Patreon!
Become a patron at Patreon!