Have you ever wondered how rainbows magically appear in the sky after a storm? 🌈 With just a few simple materials, you can create your very own rainbow at home and learn the science behind it!
How to Make a Rainbow
Rainbows are created through a process called refraction. When light passes from one medium to another—like from air into water—it bends, or refracts. As it bends, the light separates into different colors because each color travels at a different wavelength.
Red light has the longest wavelength, which means it bends the least, while violet has the shortest wavelength and bends the most. This separation of light into its component colors is what we see as a rainbow. 🌈
Think about the rainbow in the sky after a storm. When sunlight hits raindrops, the light slows down and bends as it enters the water. As it exits the raindrop, the light is split into the seven colors of the visible spectrum: red, orange, yellow, green, blue, indigo, and violet. You can recreate this process with everyday items to see a rainbow up close!
💡Explore more light activities here.
Grade Level Recommendations:
- Kindergarten – 2nd Grade: Hands-on exploration of light and color, perfect for younger learners to explore and enjoy.
- 3rd – 5th Grade: Dive deeper into light refraction and the science behind rainbows with experiments that encourage critical thinking and observation.
Fun Ways to Make Rainbows at Home
Here are a few exciting ways to create rainbows with materials you probably already have!
YOU WILL NEED:
- White Paper
- CDs
- Flashlight
- Colored Pencils
- Prism or Crystal
- Water and Cup
💡How about garden hoses on a sunny day? Create a stream of water droplets with your thumb over the opening of a hose on a sunny day, and watch the rainbow appear!
1. CD and Flashlight Rainbow
How It Works: Shine a small flashlight onto the surface of a CD. The grooves on the CD act like a prism, splitting the white light into its rainbow colors. Move the flashlight around and watch the colors change!
Science Tip: CDs reflect light, and when light hits the grooves, it refracts and creates the visible spectrum—just like in real rainbows.
2. Prism Rainbow
How It Works: Use a crystal or prism with sunlight to make rainbows appear all around you. The light bends through the different angles of the prism, splitting into the colorful rainbow spectrum.
Science Tip: A prism works like raindrops in the sky. As light enters the prism, it bends and separates into different colors. The longer the prism, the more vibrant the rainbow!
3. Rainbow STEAM Activity (Science + Art)
How It Works: Lay a CD on a blank white piece of paper and use colored pencils to match the colors you see reflected. It’s a fun combination of science and art! What colors of the rainbow can you spot?
Science Tip: Different angles of light create different hues! Try moving the CD and flashlight to see how the rainbow changes.
4. Crystal and CD Rainbow Combo
How It Works: Combine the CD and prism to make even more vibrant rainbows! Shine the flashlight through the crystal onto the CD and watch the rainbow dance across the room.
Science Tip: Light travels at different speeds through different materials, which causes it to bend. This bending is called refraction, and that’s how we see rainbows!
5. Flashlight, Water, and Paper Rainbow
How It Works: Fill a clear cup with water, place it on top of a box, and shine a flashlight into the water. Hold a piece of white paper nearby and watch as a rainbow appears on the paper. Try changing the angles of the light to create different effects.
Science Tip: As light moves from air to water, it slows down and bends, creating a rainbow. You’re recreating the same effect that happens in raindrops after a storm!
6. Explore Light Science with Flashlights
How It Works: Give your child a flashlight and encourage them to experiment with bending light. Try creating shadow puppets or using different objects to see how light moves and changes.
Science Tip: Light can be absorbed, reflected, or refracted. Kids can explore how light interacts with different objects and surfaces by experimenting with a flashlight!
💡 CHECK OUT: Shadow Puppets
Explore More Rainbow Science
There’s no wrong way to experiment with rainbows! Let your kids explore the magic of light and color, and encourage them to ask questions about what they see. 🌈 Curious minds can also check out our rainbow-themed STEAM activities for more fun! Download this free rainbow coloring page.
More Fun Light Activities
Make a color wheel spinner and demonstrate how to make white light from different colors.
Explore light with an easy DIY spectroscope.
Explore the reflection of light with a simple DIY kaleidoscope.
Learn about the refraction of light in water.
Set up a simple mirror activity for preschool science.
Learn more about the color wheel with our printable color wheel worksheets.
Explore the constellations in your own night sky with this fun constellation activity.
Make a DIY planetarium from simple supplies.
Helpful Science Resources
Here are a few resources that will help you introduce science more effectively to your kids or students and feel confident presenting materials. You’ll find helpful free printables throughout.
- Best Science Practices (as it relates to the scientific method)
- Science Vocabulary
- All About Scientists
- Free Science Worksheets
- DIY Science Kits
- Science Tools for Kids
- Scientific Method for Kids
- Citizen Science Guide
- Join us in the Club
- Printable Science Project Pack 👇
Thankyou for such easy ideas to explore rainbows