Walking Water Experiment
Want to see water defy gravity? Try our mind-blowing walking water experiment! We’ll use paper towels as a secret bridge to make colorful water climb and mix in empty cups. It’s a super easy and splashtastic science adventure for curious kids!

Science experiments don’t have to be done with expensive chemicals, glass beakers, or other fancy tools. You can easily create an amazing experiment with water, food coloring, paper towels and cups!
Your little scientists are going to love watching the magic rainbow creep onto the paper towels. Through the absorption process, colored water will “walk” up a narrow strip of paper towel creating the coolest rainbow experiment ever. This is why it’s called the walking water experiment.
We love doing kid-friendly science experiments around here. Learning How to Make Rock Candy is a favorite experiment for sure, and then this cool rainbow experiment with water comes along and steals the show! It really is so cool to watch and always gets the kiddos interested in learning. You can use this experiment in the classroom, during craft time, for homeschool, or simply as a cool experiment when you need an indoor activity.
Your kids will learn the phenomenon of capillary action, learn about the properties of water, and begin to learn color theory! Have them make a hypothesis before the experiment so that they can learn the whole scientific process.
Why You’ll Love This Experiment
- Watching the food-coloring dyes combine is so much fun! This is a great experiment to introduce your kids to the exciting world of science.
- It is actually really easy to do this experiment and you likely already have all of the supplies you need sitting in your house.
- Kids of all ages can do this experiment. Setup is really easy and as long as you follow the step by step instructions, you’ll be good to go!
How Does The Walking Water Experiment Work?
Water moves through the paper towels through a process called capillary action. This is the same process that helps plants pull water up from their roots. The leaves are hydrated through the capillary process by pulling up water from the plant’s roots.
The water molecules will be pulled up into the small fibers of the paper towels and down into the empty cups. When the different colors of water mix, it creates different colors making a fun rainbow!

Supplies For Walking Water Experiment
- Food coloring – I recommend using liquid food coloring and not gel for this experiment. You can technically use whatever colors you want, but if you want it to create a rainbow you’ll need to use red, yellow and blue.
- Water – You don’t need cold water or hot water, just room temperature will work for this science experiment.
- Kraft paper – Use some brown kraft paper to help protect your work space from spilled water, splashes and stains as you do this fun science experiment. You can also use a disposable plastic tablecloth or a baking sheet to contain the mess.
- Clear plastic cups – Grab a pack of cheap plastic clear cups in the aisle where paper products are sold.
- Scissors – You’ll need some scissors to cut paper towels into narrow strips.
- Paper towels – I recommend grabbing a half-sheet paper towel roll so that it is easier to cut up multiple narrow strips of paper towels. Don’t use printed paper towels, just use plain. I recommend that you don’t use super flimsy and thin paper towels either.
How To Do The Walking Water Experiment
Arrange 6 plastic glasses of equal height in a circle or a straight line. Different arrangements will work as long as you place the paper towels correctly. They’ll need to be placed closely together but they shouldn’t touch.
Pour water into every other cup until they are filled halfway with water. There should be an equal number of water-filled cups and empty cups.
Add a few drops of red food coloring to the first cup, a couple drops of yellow food coloring to the second cup of water, and a few drops of blue food coloring to the third. Repeat the colors or create a new combo if you have more cups.


Fold the paper towels lengthwise to increase their strength. You’ll need ½ of the paper towel for each of the cups, you can trim them if necessary.
Place one end of the paper towel strip into a cup of colored water and the other end into an empty cup next to it. Make sure the paper towel touches the bottom of each cup. Repeat this process until all of the cups are connected with paper towels.
Over time, you’ll begin to see the colors “walk” up the paper towel fibers and into the empty cups. New colors will start to form and mix in the empty cups.





Pro Tips
- Try not to have the cups filled with water at different heights. Each water-filled glass will be important to keep at a certain water level and not overfill it.
- Be careful with what colors you use because some won’t mix well and could create some other weird colors. But that could also just be a fun part of the experiment!
- Ask older kids who can write (or write down for the little ones) to jot down what they can see as the transfer happens.

This rainbow walking water experiment is such a blast to do with your kids! Enjoy watching the scientific magic happen and the ear to ear smiles from your young scientists.

Walking Water Experiment
Ingredients
- 6 small, clear glasses
- paper towels
- Food coloring blue, red, and yellow work well
- Water
- Scissors
- Kraft paper or tray or surface that can get wet
Instructions
- Arrange 6 cups in a circle or a straight line close together, but not touching.
- Fill every other cup about halfway with water. There should be an equal number of water-filled and empty cups.
- Add the red color to the first cup, the yellow color to the second, and the blue color to the third. You can repeat the colors or create a new combination if you have more cups.
- Fold the paper towels lengthwise to increase their strength. You’ll need ½ of the paper towel for each pair of cups. Trim the paper towel if necessary.
- Place one end of a paper towel into a cup with colored water and the other end into an empty cup next to it. Make sure the paper towel is touching the bottom of both cups. Repeat this process, connecting all the cups with paper towels.
- Over time, you’ll see the colored water “walk” up the paper towel and into the empty cups. You’ll observe new colors forming as the colors mix in the empty cups. For example, red and yellow will create orange, blue and yellow will make green, and so on.
- Talk about what's happening! The water moves through the paper towels through a process called capillary action. This is the same process that helps plants pull water up from their roots.
More Fun Activities
- Want some more fun science experiments? This Frozen Bubbles activity is so much fun when you can bundle up and get outside on a chilly day.
- Skip out on the store-bought slime and make this Homemade Slime instead. It only takes minutes to put together and keeps the kids busy for hours.
- This Fluffy Slime is so much fun to play with and your kids will love that they get to make it all from scratch. It’s such a great sensory activity for kids of any age.
- DIY Bird Feeders are really easy to make and are the best spring time activity! Watch all the little birds come and eat.

