Where does the water spraying from your faucet come from? It comes from lots of faraway places, but to reach everyone’s sink, it has to be pumped up into a “water tower,” a giant tank high off the ground. When the water comes back down, it pushes down on itself and rushes through the underground pipes to every building in town. The higher the water tower, the harder it pushes and the faster it sprays! So our fans Elijah and Shane S. asked, how much water does a water tower hold? Towers come in all sizes, but each holds about 1 day’s worth of water needed for its town. It can be a million gallons or more — that’s about 50 swimming pools!
Wee ones: Hold a glass under a faucet, turn on the water, and count “1 alligator, 2 alligator…” until it’s full. How many seconds (alligators) did it take? Try again running the water faster!
Little kids: If it takes 8 minutes to fill a bucket of water from your faucet, but 10 minutes to fill your bathtub, which one takes longer to fill? Bonus: How much longer does the tub take?
Big kids: Can you “spell” the number 1 million in digits? Bonus: If a water tower starts with 1 million gallons, and then 100,000 gallons are used that morning, how much water is left in the tank before it refills?
Answers:
Wee ones: Different for everyone’s faucet…see what you get!
Little kids: The tub takes longer. Bonus: 2 minutes longer (10-8).
Big kids: 1,000,000. Bonus: 900,000 gallons.

Laura Bilodeau Overdeck is founder and president of Bedtime Math Foundation. Her goal is to make math as playful for kids as it was for her when she was a child. Her mom had Laura baking before she could walk, and her dad had her using power tools at a very unsafe age, measuring lengths, widths and angles in the process. Armed with this early love of numbers, Laura went on to get a BA in astrophysics from Princeton University, and an MBA from the Wharton School of Business; she continues to star-gaze today. Laura’s other interests include her three lively children, chocolate, extreme vehicles, and Lego Mindstorms.