Sometimes restaurants give out “kid menus” and crayons. The problem is, when kids leave, the restaurant can’t give the used crayons to other kids, because that spreads germs. Sadly, they have to throw out these new crayons. Between 45,000 and 75,000 pounds of new crayons go into landfills every year. So one dad, Bryan Ware, started The Crayon Initiative: Restaurants and schools ship him their leftover crayons, and he melts them, pours the wax into molds, and lets them cool to make thicker, triangle-shaped crayons. He gives them to kids in hospitals to cheer them up. So you can send any extra crayons you have to The Crayon Initiative to help make more and to save the environment!
Wee ones: How many sides does a triangle have?
Little kids: If you can fit 7 regular crayons in one hand but just 3 of the fat ones in the other, how many can you hold altogether? Bonus: How many more do you have in one hand than the other?
Big kids: If every 3 regular crayons can be melted to make 2 fat triangle ones, how many new crayons can he make from a dozen regular ones? Bonus: If 20 restaurants in your town each serve 100 kids a week and give 4 crayons to each, how many crayons could they save together each week?
The sky’s the limit: Bryan’s molds make 96 crayons at a time. If the 96 slots are in neat rows across and down, and there are at least 4 rows in each direction, how many pairs of numbers of rows across and down could there be? (You don’t have to double-count the pairs where the numbers are the same but switched.)
Wee ones: 3 sides.
Little kids: 10 crayons. Bonus: 4 more regular crayons than fat crayons.
Big kids: 8 fat crayons, since you have 4 sets of 3 regulars that can now make 4 sets of 2 big ones. Bonus: 8,000 crayons!
The sky’s the limit: There are just 3 possible truly different ways to line up the rows. This is a factoring problem: what numbers equal to or greater than 4 and larger divide evenly into 96?
4 rows of 24 each
6 rows of 16 each
and 8 rows of 12 each.
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.