Watch water seemingly defy gravity to blend colors together, creating a rainbow in this fun and exciting STEM walking water experiment kids can do themselves!
I don’t know about you, but I struggle with doing science experiments with my kids. They are always so much more time-consuming, messier, and harder than I think they’ll be.
As much as I want to do them, I always feel too busy, too tired, or too frustrated to actually accomplish it! Can you relate?
Do you want to allow your kids to do science experiments and learn about the world around them but don’t want to deal with the mess or the hassle? Here is the perfect solution: a walking rainbow experiment.
That’s why when I came across this experiment, I just knew that:
- I could do it (it’s not too hard, complicated, or time-consuming!)
- The kids would LOVE it (the rainbow colors really make the project exciting)
In addition to pictures, I also have a video for you so you can see just how cool (and easy) this walking water science experiment is!
Science is Fun: Walking Water Experiment
I’m a huge fan of science because I think it helps us understand the world around us. And because kids are so inquisitive and hands-on, science experiments help them to get an even better grasp of how things work around them.
We have tried the classic exploding volcano and several other science experiments. And while I think they have been fun learning experiences for my boys (boys love a good mess, right?), they have more often than not felt like more work than they were worth.
That’s why I LOVE this walking water science experiment! It’s just the perfect amount of work (hardly any at all), but the payout is huge.
And I gotta say – the rainbow colors are mesmerizing and so worth it!
4 Reasons to do this Walking Water Activity
I actually saw this rainbow paper towel experiment quite a while ago but put it off.
I’m not only eating my words (ok, thoughts) but I’m also kicking myself for not doing this one sooner. It’s now my favorite experiment – seriously do it right away. Here’s why:
My Kids Loved It
What’s not to love about mixing colors together, right? Haven’t your kids ever mixed sauces or sodas or juices together to see what they look like when blended?
And honestly, if it’s not fun enough, then the kids won’t be interested which makes doing science experiments even more of a pain. I’m not going to drag my kids into doing something that’s not interesting!
If your kids love rainbow colors, be sure to make these Easy Colorful Rainbow donuts
It Took Just the Right Amount of (my) Time
As much as I sometimes hate it, my “free” time is sometimes very limited.
This walking water experiment is perfect because it just takes a few minutes to set up and then the fun part is in the watching…rather than the opposite of taking an hour to set up for only 3 seconds of wow factor.
Love crafts and easy DIY projects? Grab this mini activity book for more by clicking the image below – free! 👇
It’s Cheap
This doesn’t take any big investments, which I love. Simple supplies like plastic cups, paper towels, and food coloring = my kind of project!
I hate those projects that require you to buy some $20 or $30 part…and to make it worse, require tons of work with 3 seconds of “cool”. Ugh.
It’s Simple
No “Walking Water Experiment For Dummies” book required! All the instructions you need are below.
Supplies Needed for this Walking Rainbow Activity
Here’s everything you’ll need to get the job done. I’ve included links to help find certain things faster. Some links below may be affiliate links which means that you do not pay anymore, however, a small commission will go to this site.
- 5 clear glass (like mason jars) or plastic cups
- Red, blue, and yellow food coloring
- Scissors
- 2 paper towels
- Water
- Spoon
Pro Tip: While you can use regular size paper towels, I highly recommend the pick-a-size paper towels because you use less for each cup. However, if you only have full sheets take extra time to cut them in half.
In theory, more absorbent paper towels work better. But, I buy cheap off-brand ones, and our water moved quickly from cup to cup, so I am not sure how vital that tip is. Maybe it goes a little quicker with more absorbent paper towels?
Watch The Walking Water Project Video!
Check out this short video I made showing you how cool the walking water science experiment is! Then follow the instructions below.
How to do Walking Water Experiment
Follow these directions, and you’ll have your own rainbow in no time! Feel free to grab the printable experiment directions below for easy reference when you’re ready to do it.
Step 1
Place 5 cups in a row and pour water in the 1st, 3rd, and 5th (odd-numbered) cups. Fuller is better, so fill them about ¾ full.
Step 2
- Add 5 drops of red food coloring to the 1st cup and the 7th cup.
- Add 5 drops of blue food coloring to the 3rd cup.
- And 5 drops of yellow food coloring to the 5th cup.
Step 3
Take the paper towel half-sheet (you’ll need 6 total) and fold it in half (lengthwise) and repeat the folding process until your paper towel strip is 1-2 inches wide.
Step 4
Trim off a bit of the length so that there isn’t much excess paper towel that will stick up in the air between each cup. This will help the water walk faster.
Step 5
Place one half of a rolled paper towel in the 1st cup and place the other half in the cup next to it (the empty 2nd cup). Then another paper towel from the 2nd cup and into the full 3rd cup.
Continue this process until you reach the end.
Step 6
Watch the cups to find out what begins to happen. It shouldn’t take long before you are able to see the colored water begin to travel up the paper towel.
You can sit there and literally watch the cups, or walk away for about 5 minutes and come back to check on the progress. The water will stop moving from cup to cup once all the cups are about the same level of fill.
Rainbow Water Experiment Notes
IMPORTANT ADJUSTMENT – I only had 5 cups when I did this experiment, so I had to modify it slightly as you can see in the photos. So here’s what I did: I put the yellow into the last cup and then added 3 drops of red coloring to the yellow cup to make the orange.
It looks even more amazing when you can do it with 7 cups, but I wanted to show you that you can still do it well with 5 cups.
FOOD COLORING – You don’t need to use food coloring in order for this project to work. However, doing so exponentially takes the “fun” level way UP! It helps the kids to see the “walking” part too 😉
SUPERVISE COLOR DISTRIBUTION: Try to use the same amount of food coloring in every cup. If you let your kids add the food coloring and they are more “liberal” with one or two, simply add the difference to the remaining cups!
Love crafts and easy DIY projects? Grab this mini activity book for more by clicking the image below – free! 👇
How Long Does the Walking Water Experiment Take?
The process takes approximately 30-45 minutes to move completely.
But it’s amazing to watch the water move upwards and over into the empty cups, creating new colors along the way.
Important Questions to Ask About This Walking Water Experiment
This may be a fun activity, but it IS a science experiment! What can the kids learn from it?
Consider asking your kids these questions to help them learn more and think through this project:
- What do you think will happen with the water?
- What do you think will happen to the colors?
- How can water move up against gravity?
Talk About Colors
Not only do the colors make this experiment even more fun, but it’s great opportunity to teach the kids about primary colors (red, yellow, blue) and secondary colors (made by combining primary colors: orange, green, purple).
Check out the colorful rainbow!
How Does the Walking Water Experiment Work?
Have you heard of the process of capillary action?
The paper towel is made of fibers. Water travels through the gaps in the fibers kind of like straws (capillary tubes) pulling the water upward.
Why? Because the water is attracted to the paper towel fibers and pulls other water molecules along with them as water is pulled through the fibers.
These attractive forces between the water molecules and the paper towel forces pulls the water up against the pull of gravity.
Real World Application? This is the exact process that draws water from a plant’s roots to the leaves at the top of the tree or plant.
Love crafts and easy DIY projects? Grab this mini activity book for more by clicking the image below – free! 👇
Walking Rainbow Water Activity Final Thoughts
If you have been wanting to do some science projects with your kids but don’t want to deal with the hassle, the mess, or the time commitment of babysitting a science experiment, this is THE project to do.
Plus, the wow factor is out of this world!
And a bonus is that it’s not just kids who love this walking water science experiment! Adults find it pretty enthralling too😁
Pin for Later!
More From Made in a Pinch:
- 14 Games to Play When Bored (beyond belief) at Home
- 75+ Fun Things to do With Kids at Home (updated for self-isolation)
- Indoor Sensory “Grass” Play Activity
Rainbow Walking Water Experiment
A fun and easy STEM project for kids to teach them about colors and capillary action!
Ingredients
- 5 clear glass (like mason jars) or plastic cups
- Red, blue, and yellow food coloring
- Scissors
- 2 paper towels
- Water
- Spoon
Instructions
Place 5 cups in a row and pour water in the 1st, 3rd, and 5th (odd-numbered) cups. Fuller is better, so fill them about ¾ full.
Add 5 drops of red food coloring to the 1st cup and the 7th cup. Add 5 drops of blue food coloring to the 3rd cup. And 5 drops of yellow food coloring to the 5th cup.
Take the paper towel half-sheet (you’ll need 6 total) and fold it in half (lengthwise) and repeat the folding process until your paper towel strip is 1-2 inches wide.
Trim off a bit of the length so that there isn’t much excess paper towel that will stick up in the air between each cup. This will help the water walk faster.
Place one half of a rolled paper towel in the 1st cup and place the other half in the cup next to it (the empty 2nd cup). Then one from 2nd cup and into the 3rd cup and so on until you reach the end.
Watch the cups to find out what begins to happen. It shouldn’t take long before you are able to see the colored water begin to travel up the paper towel.
Notes
The entire process can take up to 45 minutes, but it's fun to watch as the colors travel!
I like the way this project looks. I’m doing this project this year for my 5th grade science fair project.
Hi Michael! That’s terrific! I hope it turns out well – good luck in the science fair!
This takes me back! What a great experiment to do with kids. I’ll have to get my kids doing this one.
Such a fantastic project! Definitely need to try these out.
What a fun project! I’ll have to try this one out with my kids.
Now, this looks fun. My daughter would enjoy this. She loves anything that allows her to use my food coloring.
I love this idea. Gonna try this with my daughter. She’s at the stage that she wants to know everything and i know she will enjoy this.
This is great! It’s so simple yet has a big impact on kids. Mine will love to watch the color travel and probably turn it into a race to see which color will make the rainbow first.