Whoa — is that bus really running on 2 giant toy batteries? Nope — that’s a trick of the eye. Those batteries are painted on. It’s amazing what you can do with paint if your artwork looks real. On the bus below it, someone painted around the wheels to make them look like eyes. And in the third, the stretchy part of the bus looks like the bendy part of a toothbrush. Buses are a good 40-50 feet long, so these eyes, batteries and brushes are way, way bigger than real ones. How much bigger are they?
Wee ones: How many batteries do you see on the first bus?
Little Kids: If the bus tire is 3 feet wide and the eye painted around it is 5 feet wider, how wide is that eye? Bonus: If your whole body is 4 feet tall, how much longer is that eye than you if you lie down next to it?
Big kids: If the bus toothbrush is 10 feet long and your own toothbrush is just 8 inches, how many inches longer is the bus toothbrush? (Reminder: 1 foot has 12 inches.) Bonus: If the 2 eyes together stretch across 20 feet of the bus, and your own eyes span just 6 inches of your face, how many times as wide is the bus’s “face”?
Wee ones: 2 batteries.
Little kids: 8 feet wide. Bonus: 4 feet longer.
Big kids: 112 inches longer, since the big toothbrush is 120 inches long. Bonus: 40 times as wide!
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.