One really fun summer sport is surfing. You walk out into the ocean, stand on a long skinny surfboard, and try to ride it as the waves push you along. It’s very hard not to fall off — so imagine riding it with dozens of other people! These 66 people in California squeezed onto a 42-foot-long surfboard and rode it for a whole 15 seconds, beating the world record for the most surfers on the biggest surfboard. The board weighed 1,300 pounds, but of course had to carry 10,000 pounds of people. We hope once everyone fell off that somebody remembered to grab the surfboard.
Wee ones: If you surf the 1st wave, then skip the 2nd, then ride the 3rd, then skip the 4th, what do you do on the 5th wave?
Little kids: The surfboard was 11 feet wide, maybe almost as wide as your room! Lie down head to toe with a grown-up, and guess whether the 2 of you could stretch across that board. If you lay across it, by how many feet would you fall short of stretching across? Bonus: Once the 1st surfer fell off, how many of the 66 surfers were still hanging on?
Big kids: If the surfers weighed 10,100 pounds and the board weighed 1,300 pounds, how much did that weigh all together? (Hint if needed: Start with the board weighing just 1,000 pounds.) Bonus: If your regular surfboard is only 1/6 as long as this monster 42-foot one, how long is your board?
Wee ones: You ride the 5th wave.
Little kids: See if your height in feet + a grown-up’s height add to 11. Bonus: 65 surfers.
Big kids: 11,400 pounds. Bonus: 7 feet long.
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.