Walking colors

From the house

• 3 clear glasses or jars
• Water
• Yellow and blue food coloring
• 2 paper towels

How to play

1. Line up the glasses: one nearly full of yellow water, one empty, and one nearly full of blue water.
2. Fold each paper towel into a long strip and bridge it from a full glass into the empty middle one.
3. Watch the colors start to climb, then leave it: it takes about an hour to reach the middle glass.
4. Check after an hour and again in the morning: what color is in the middle, and how did it get there?

Fit it to your child

• Easier: Use one full glass and one empty glass with a single strip, and check it together after dinner.
• Harder: Make a ring of six glasses, red, yellow and blue with empty ones in between, and they predict each new color before it appears.

Words to use

• climb
• soak
• mix
• wait
• green

Why it helps

Water creeps up through the tiny gaps in the paper and carries the colors to mix in the middle, and checking back later teaches them that some experiments need patience.