Have you ever seen a real rainbow? Maybe a little one on the wall from sun shining through angled glass, or a giant one in the sky (which you find by standing with your back to the sun, then looking forward 40 degrees to your left and right). A single rainbow has stripes of all the colors — red, orange, all the way to violet — but sometimes it’s stacked under another backwards rainbow that runs from violet to red. That’s called a double rainbow, and it’s very special because it’s so rare. That’s why people love this photo of two double rainbows. Amanda Curtis saw it over a train station in Long Island and quickly snapped a picture. No one is sure how the sun made these shapes, but we’re lucky the camera caught it before they disappeared.
Wee ones: A rainbow has red, orange, yellow, green, blue, and purple. Try to find 1 thing in your room of each color. How many things did you find in total?
Little kids: Some say the rainbow has 1 more color than the above: “indigo” (between blue and purple). How many colors does that rainbow have? Bonus: You can take any 2 of the “primary” colors — red, yellow and blue — and mix them to make a “secondary” color (like orange, which mixes red and yellow). How many different pairs of primary colors can you choose to mix?
Big kids: If you could see 7 sharp stripes in each of the 4 rainbows here, how many colored stripes would you see in total? Bonus: Rainbows in the sky usually don’t last long. If the rainbow appeared at 6:58 pm and lasted just 5 minutes, when did it disappear?
Wee ones: 6 things, if you find one of each of those colors. Items might include socks, Lego blocks, other toys, and book covers.
Little kids: 7 colors. Bonus: 3 pairs: red+yellow, yellow+blue, and red+blue. Those give you orange, green and purple — the other 3 colors in the 6-color rainbow!
Big kids: 28 stripes. Bonus: At 7:03 pm.
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.