Line up all your jars in a triangle.

Pour 1 cup of water into each jar. 

Add a few drops of each food coloring into their own jar and stir until the water has a vibrant color.

Cut your paper towels into small rectangles just long enough to reach each water.

Use your paper towel strips to connect your jars. Red to Yellow - Yellow to Blue - Blue to Red

Watch the paper towels carefully. What is happening to the paper towel?

Come back in a little bit. What do the paper towels look like now?  Is the water in each cup the same color?

Observe what happens over the next 24 hours.

Followup Experiment: 

Instead of using 3 and observing the changes, use 5 or 7 jars.  Fill every other one with water.  Add food coloring to the jars with water.  Do not use the same color twice in a row.

Follow the same activity instructions, but use paper towels to connect a water-filled jar with an empty jar.

What happens to the empty jars?

Try another brand of paper towels.

How does the water walk if you use a straight line instead of a circle?

What if you put different amounts of water in the jars?