It’s St. Patrick’s Day, the day that people wear green, dye their hair green, and squirt food coloring in the toilet to make the water green. People also turn all kinds of food green, too, and we don’t mean lettuce or broccoli. We mean green bagels, green beer for the grownups, and so on. You can make your milk green for your cereal in the morning, and green icing for cupcakes – just take white icing and mix in some food coloring. Remember, food coloring has superpowers: you need only 2-3 drops to tint a whole big bowl of frosting! Now let’s see how many green snacks we can make to celebrate.
Wee ones: Green is one of the colors of the rainbow. The others are red, orange, yellow, blue, indigo and purple. How many other colors is that? Count along with a grownup!
Little kids: If you sneak 3 drops of food coloring into your brother’s cereal and 3 drops into your sister’s cereal, how many drops did you drip? Bonus: How many drops would you put in your own cereal to get to a total of 10 drops?
Big kids: If you have a dozen cupcakes (that’s 12) and put green icing on half of them, how many have green icing? Bonus: If you put 24 cupcakes on a tray in 4 neat rows of 6, and only the cupcakes around the edges get green icing, how many cupcakes are green? What are different ways to figure that out?
Wee ones: 6 other colors.
Little kids: 6 drops. Bonus: 4 more, because 6 + 4 = 10.
Big kids: 6 cupcakes. Bonus: 16 cupcakes: 6 in the top row, 6 in the bottom row, then 2 on the left side and 2 more on the right side. Another way to do it: you will have a rectangle in the middle of 2 x 4 = 8 white cupcakes, and can subtract that from 24 to get the rest.
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.