Simple Rainbow Science Experiment for Kids

Here is a Simple Rainbow Science Experiment for Kids that is quick and easy to do with young students! Making a rainbow is a great way to study reflection, refraction, and dispersion of light. This would be a fun experiment to try around St. Patrick’s Day or perhaps while studying a weather unit. Students may want to draw or color their rainbows in a science notebook as well!

*Pair this with our St. Patrick’s Day Centers & Activities for Pre-K/Kindergarten

Simple Rainbow Science Experiment for Kids

Bring some hands-on science fun to your classroom with this easy, no-mess experiment! You can do this science experiment in the springtime or anytime!

Teach your early learners all about reflection, refraction, and dispersion of light!

To make your own rainbow, you will need:

• a glass of water
• a sunny window
• a sheet of white paper

How to make your rainbow:

To begin, invite your child to place a glass of water near a sunny window. For best results, look for a direct beam of sunlight. When the Sun is low in the sky (early or later in the day) works best.

Next, place a sheet of paper on the other side of the glass. You should notice a rainbow that is projected onto the sheet of paper!

Why it works:

Sunlight is made up of various wavelengths, and each wavelength appears as a different color. The water is used to reflect and refract light. As the sunlight passes through the water, the sunlight is separated into a spectrum of colors forming a rainbow.

RELATED RESOURCE: March Math & Literacy Printables

Questions to consider:

• Can you think of another way to make your own rainbow?
• What happens if you change the shape or size of the glass of water?
• What happens if you place the paper further away from the glass?
• Add a few drops of food coloring to the water. Are you still able to make a rainbow?
• Replace the water with mineral oil, what happens?
• If there were no signs of rain, would you be able to see a rainbow outside? Why or why not?
• Draw and color your observations in a notebook.

Are you looking for more science experiments? You might also like our Multicolored Flower Science Experiment!