When you’re eating a yummy snack and wish you could share it with a friend, wouldn’t it be great if you could just slap a stamp on it and stick it in the mail? It turns out you can, with one food: coconut. On the small Hawaiian island of Molokai, the Hoolehua Post Office gives out free coconuts for people to ship to their friends. No box, no envelope — you just stick a stamp onto the coconut. The “Post-a-Nut” postage costs between $9-13 depending on the coconut’s weight: If you shake a coconut and hear juice sloshing around inside, that means it’s still fresh enough to eat — but it will weigh more since it hasn’t dried out. For a fresh coconut snack, it’s totally worth it.
Wee ones: If you mail a coconut to each of 2 friends and grab one for yourself, how many coconuts do you get?
Little kids: If you could ship a coconut for $10 and a watermelon for twice as much, how much would it cost to ship the watermelon? Bonus: How much do you pay to ship both?
Big kids: 7,000 people live on Molokai. If each one sends a coconut to 3 friends, how many coconuts get shipped out? Bonus: If out of 400 nearby trees, 1/2 the trees grow 10 coconuts each while 1/2 grow 20 each, how many coconuts can the post office mail?
Wee ones: 3 coconuts.
Little kids: $20. Bonus: $30.
Big kids: 21,000 coconuts. Bonus: 6,000 coconuts: 2,000 from the first 1/2, and 4,000 from the 2nd set.
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.