The ice cream cone is almost as great an invention as ice cream itself. It was born in 1904 when a baker wrapped a waffle around a scoop of ice cream, because the ice cream cart guy had run out of bowls. But that wasn’t enough: someone in Korea then invented the ice cream tube. Unlike the cones in the picture, it’s a hollow J-shape that holds ice cream all through the tube, with the yumminess peeking out at both the high and low ends. Now you can switch back and forth easily between two flavors as you eat. People love the J cone because it drips less, since most of the ice cream is inside it…and you can fit more ice cream, too!
Wee ones: What shape does a regular pointy ice cream cone look like from the side?
Little kids: If you can fit 2 scoops of ice cream in a regular cone, but 4 more scoops than that in the crazy J, how many scoops does the J cone hold? Bonus: If you then eat halfway through your J cone, how many scoops have you eaten?
Big kids: If a shop has 3 choices of flavors for the top end and 6 choices for the bottom, how many different combos can they serve you? Bonus: If instead they serve 5 flavors in total and you pick 2 *different* ones for the top and bottom, now how many different combos could you get?
Wee ones: A triangle.
Little kids: 6 scoops. Bonus: 3 scoops.
Big kids: 18, since each of the 3 top flavors could go with any of the 6 at the other end. Bonus: 20 different pairs, since once you pick a flavor, you’ll have 4 others for the top, and you can do this for each of the 5 flavors.
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.