That top picture looks like a photo of a paper crane, just like the 2 origami birds above it. But it’s a trick of the eye: it’s a picture of hundreds of thousands of birds! They’re lined up to make a 40-foot picture of a giant one. Where did they come from? After the Japan earthquake and tsunami in 2011, Students Rebuild invited kids to fold cranes and mail them in. Then artist Vik Muniz made a giant mosaic out of them. The Bezos Family Foundation promised to give $2 for every bird sent to help people in Japan, up to $200,000. Kids mailed more than 2 million cranes: the smallest was the size of a thumbtack, and the biggest was 3 feet wide. Best of all, the cranes came from all 50 states and 38 other countries! These birds can’t fly, but they certainly can help.
Wee ones: What shape do the cranes’ pointy wings look like?
Little kids: If you send 2 big blue cranes and 4 little yellow cranes to Vik, how many paper cranes do you send? Bonus: If the cranes came from the U.S. and 38 other countries, how many countries was that in total?
Big kids: How do you write “2 million” in all digits (numbers)? Bonus: So many kids sent in cranes that the Bezoses doubled the $200,000 limit, and another person gave $100,000! How much money was given in total?
Wee ones: Triangles.
Little kids: 6 cranes. Bonus: 39 countries.
Big kids: 2,000,000. Bonus: $500,000 (5 hundred thousand dollars)!
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.