STEM Activity: Make a Rainbow
Create an amazing, interactive rainbow using simple materials!
- Dark room
- Clear glass vase, container or cup
- Flashlight with batteries
- Mirror, compact or back of a CD/DVD (must fit inside of the glass)
Get ready to make your own rainbow!
- Fill a glass of water and set it on a table.
- Place a mirror (or CD/DVD) inside of the glass at an angle, reflective side up.
- Turn off the lights in the room, and use curtains to darken the room, if necessary.
- Turn on your flashlight.
- Aim your flashlight at the submerged mirror and admire your rainbow.
- Try changing the angle of the flashlight, as well as the distance of the light to the glass, and see how it changes the shape and direction of the rainbow!
Educators: Use this activity in the classroom with these modifications
Explore the possibilities that a rainbow offers by experimenting with different types of materials in the classroom. Offer children small mirrors, DVDs and CDs, along with different sizes or types of flashlights to see how it impacts the colors, shape and size of the rainbow. Challenge them to project their rainbow onto different surfaces or even each other.
What are we learning?
When light passes from one medium (e.g., air) through another medium (e.g., water) of a different density, it refracts. White light passing through water separates into the individual visible colors that it’s comprised of and creates a rainbow! When we conduct experiments of this nature, we are exploring more than just science concepts — we are exploring mindset, an important aspect of invention. What do you see when it rains and then quickly becomes sunny? A rainbow! Sometimes inventors feel like what they are working on is silly, pointless, or even impossible. However, successful inventors do not give up. They navigate their way through the storms and are often rewarded with the vibrant rainbows that follow.