My daughter asked me to do the “walking water” demonstration this past week. It’s such a fun and simple little “experiment.”  She was old enough this time to do it herself. I had a couple of people ask me about it, so I thought I do a short tutorial on how to do it.

You need

• 7 clear cups
• water
• food coloring
• paper towels

First set the cups up in a row with a little space between each cup.

Then pour water in every other cup making sure to fill both cups on the ends.

Add the primary color dyes to 4 of the cups with water making sure that the two end cups are the same color and the other primaries are distributed into the two remaining cups.

Take a piece of paper towel (1/2 of a full size or whole of a smaller size) and fold them lengthwise twice. Repeat this until you have six folded paper towel strips.

Use the paper towels to create a “bridge” between each of the cups, making sure one end goes into a water cup and the other of each towel goes into a the adjacent empty cup.

Then you wait!  This is the hardest part, but luckily it’s not really that long. It take an hour or two at most and is so gratifying. You will see that the water has “walked” from the full cups to the empty cups and the empty cups are no longer empty, but now have the secondary colors of whatever primary colors they are adjacent to.  This provides so much to talk about from water’s special properties of adhesion and cohesion to primary and secondary colors. It can span several age ranges as well.