Introduction: Easy Magical Walking Rainbow Experiment

Have fun while learning a few basic scientific methods!

- color theory: the paper towels pull color from the base red, blue, and yellow primary color cups, the resulting mixture creates the secondary colors of green, purple, and orange, completing the rainbow.

- capillary action: Capillary action is how plants pull water from the soil and up into their leaves to keep watered.

Did you know that three basic colors can combine together to make any other color? These three basic colors are red, blue and yellow. They are referred to as primary colors. When two primary colors combine in equal amounts, they produce a secondary color.

and kids really enjoy the hands-on they get with this experiment.

For detailed information about the science behind this experiment checkout KIDDLE


6 transparent cups

Paper towel roll

gel food coloring


3 plastic spoons

Step 1: Collect Your Materials

I used 6 clear plastic cups that I had leftover from one of my kids birthday parties, but you can use drinking glasses, wine glasses. empty mason jars. or whatever you want. Youll want to make sure whatever you use that they are about the same height and are crystal clear so you can see all the colorful action.

This experiment can get a little messy so I would suggest putting down a plastic table cloth or painters plastic from the dollar store.

I used regular food-grade food coloring gel from HEB, but you can use watercolors, or other food dyes if you have them. Whatever you use make sure it will disperse in water.

a container of clear water so you can fill your cups

and several different stirring sticks a different one for each color, I just used some plastic spoons I had tucked away .

Also, it's a good idea to record your experiment I have included a free datasheet at the end of the Instructables that you can print up.

Step 2: Prepare the Colored Water

Take 3 cups and fill them with water

Once the cups are about three-quarters full add several drops of food coloring, try to use the same amount of food coloring in all the cups. You will need to add red, blue and yellow coloring to the cups.

Step 3: Place Cups in a Circle

You will now have 3 cups full of colored water and 3 empty cups..

Place all the cups into a circle and alternate them so you have a cup with colored water and then an empty one

Step 4: Place the Paper Towels

Roll the paper towels into tube-like pieces and put one end in a full cup and the other end in an empty cup.

Step 5: Like Magic

The capillary action will start happening right away. but it will take about 48 hours to complete. Once the water level is the same in all the cups and the paper towels are all wet, the water stops moving from cup to cup.

You can also try:

- the activity with different brands of paper towels, some may work better than others

- placing your cups in different arrangements instead of a circle. For example, connect three cups, initially filled with water, to an empty fourth, central cup, Or place all your cups in a straight line or triangle.

Here's a link to a free data recording sheet to keep track of what happens with your experiment.

Walking rainbow recording and datasheet

Most of all Have fun!

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