🌈 Grow a Rainbow with a Paper Towel and Washable Markers: A Colorful Science Experiment for Kids! 🌈🧪


Are you looking for a fun and colorful science experiment to do with your kids? Look no further than growing a rainbow with a paper towel and washable markers! This easy and engaging activity will have your kids amazed as they watch the colors blend together to create a beautiful rainbow. 🌈


  • 🌈 Washable markers (in rainbow colors)
  • 🧪 Water
  • 📝 Paper towel
  • 🥤 Clear plastic cup
  • 🌞 Sunlight


  1. 📝 Cut a paper towel into a strip that is about 2 inches wide and long enough to fit around the inside of the plastic cup.
  2. 🌈 Draw a rainbow using the washable markers on one end of the paper towel strip.
  3. 🧪 Fill the plastic cup about 3/4 of the way with water.
  4. 📝 Place the paper towel strip in the cup with the end containing the rainbow touching the water.
  5. 🌞 Place the cup in direct sunlight and wait for a few hours.
  6. 🌈 Watch as the colors from the markers blend together and "grow" up the paper towel strip, creating a beautiful rainbow!

Explanation: The Grow a Rainbow Experiment is an example of capillary action. Capillary action is the ability of a liquid to flow through a narrow space without the assistance of, or even in opposition to, external forces like gravity. In this experiment, the water in the cup is absorbed by the paper towel strip due to capillary action, and the water carries the colors from the markers with it as it moves up the strip, creating a rainbow effect.


  • 🖌️ Try using different types of markers to see if they produce different results.
  • 🌡️ Experiment with different temperatures of water to see how it affects the rate of color absorption.
  • 🧫 Add a drop of dish soap to the water to see if it affects the experiment.

The Grow a Rainbow Experiment is a fun and colorful science activity that kids will love! Not only is it a great way to teach them about capillary action, but it's also a beautiful way to learn about the colors of the rainbow. So, grab your washable markers, paper towel, and a clear plastic cup, and get ready to grow your very own rainbow! And, if your kids need a fun and functional backpack to carry their science experiment supplies, check out Little Monster Bags, the perfect backpack for school, playtime, and everything in between. 🎒👀

Check out the pin below from. 

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