Well actually, it's the water that walked.
Basically you take:
Line up the three cups and put water on the first and last cup, leaving the middle one empty.
Put a different color food coloring on the cups with water and prepare your tissues. Fold them in twice or thrice (so that they fit that mouth of the cups) and bend them making sure one end rests on the colored water and the other on the empty cup in the middle.
Do the same for the other cup.
Wait for a about an hour or two and you will eventually see the water "walking" to the empty cups. It's also cool to see the colors mixing together and forming new colors.
It's a simple experiment but quite fun for the little ones too!
