How to Make and Use a Sundial at Home

If you’ve ever wondered how people told time before clocks, this is the perfect project to try at home. A sundial uses the Sun’s position in the sky to track time, and by making your own, you’ll get to explore some amazing Earth science concepts in action. It’s a brilliant introduction to seasons, latitude, Earth’s rotation, and even early navigation.

This post is written especially for independent learners and homeschooling teens, but it works just as well as a guided family project.

What You’ll Need to Make your Sundial

You can grab a printable sundial kit from my store.

The kit includes:

• An easy-to-assemble sundial template
• Clear setup instructions
• Printable journal and reflection pages
• Extension activities for deeper exploration

A Southern Hemisphere version will be released soon!

How a Sundial Works

As the Earth rotates, the Sun appears to move across the sky. A sundial works by casting a shadow from a central stick (called a gnomon) onto a flat surface. As the Sun moves, the shadow shifts, and you can mark the hours based on where that shadow falls.

To make it accurate, the sundial must be:

• Aligned correctly (using true north/south)
• Tilted at the angle of your latitude
• Set using solar noon, not your digital watch!

This is where science meets the real world.

Latitude vs. Longitude – What’s the Difference?

These two terms are easy to mix up, but both are crucial for understanding time, light, and position on Earth.

• Latitude measures how far north or south you are from the equator (0°). It affects the angle of sunlight, the length of your days, and the tilt needed for your sundial’s gnomon.
• Longitude measures how far east or west you are from the Prime Meridian (0° in Greenwich, UK). This impacts your local solar time, and why solar noon doesn’t always happen at 12:00 PM on your clock.

In short:

• Latitude = Sun angle and shadow shape
• Longitude = Solar noon timing

So if your sundial seems “off,” it might be because your clock time doesn’t match your solar time — and that’s where solar noon comes in.

Create a Model to show lines of Longitude and Latitude

What Is Solar Noon?

Solar noon is when the Sun is at its highest point in the sky, directly overhead for your location. It’s not the same as 12 PM, it varies based on your longitude and time zone.

At solar noon:

• Your shadow is shortest
• The Sun is due south (in the Northern Hemisphere) or north (in the Southern Hemisphere)
• Your sundial is most accurate

You can find your solar noon using:

• The NOAA Solar Calculator
• Google: “solar noon [your location] [date]”
• Observation: track your shadow and mark when it is shortest

Why This Matters for Marine Science

Understanding how the Sun’s position changes throughout the day and year is fundamental to marine science. It influences:

• Ocean currents
• Winds and weather systems
• Tides
• Seasons and habitats

This simple sundial model introduces you to the core Earth systems, and shows how science and nature are deeply connected.

Ready to Get Started?

Use it as a:

• Short science investigation
• Entry point into seasonal study
• Extension for geography or physics topics
• Real-world journaling project

Reflect & Explore Further

The printable journal pages included in the pack will help you:

• Track and sketch shadow movement
• Connect shadow length with time of day
• Reflect on Earth’s rotation and Sun position
• Answer questions like:
  • How does latitude affect sunlight?
  • What changes at the poles vs. the equator?
  • How would this sundial work in winter?

Plus, optional extension prompts invite teens to:

• Compare results with someone at a different latitude
• Investigate oil spills and sunlight in the ocean
• Explore deeper Earth-Sun relationships

Further Ideas to Explore

• Ocean Zones in a Jar – explore density and the depths of the ocean in your kitchen
• Books for Teens Interested in Marine Sciences
• One of the ancient civilisations that used sundials was the Maya – explore their civilisations, mythology and life more with our Mayan Unit Study

Want More Hands-On Marine Science?

If your teen enjoyed this sundial activity, they’ll love diving deeper into ocean and Earth science with us.

Join the Marine Science Interest List and get:

• Exclusive activities and experiments
• Book recommendations for curious teens
• Updates on upcoming courses and free workshops
• Tips for building real science skills at home

Subscribe below and get ready to start exploring the science of our blue planet.