March 20 is pretty special, and not just because it’s the 79th day of the year. In most years March 20 is the start of spring, also called the vernal equinox. Equinox in Latin means “equal night”: on this day Earth is tilted neither towards or away from the sun, so every spot has 12 hours of both day and night. Because of that perfect tilt, people try to balance an egg on end at the exact moment of the equinox. It works — because you can balance an egg any time! Turns out eggs are also incredibly strong. While they break easily if they land on the floor, they can hold up really heavy objects when stacked between plastic cups, as shown here. It’s a game you can try today or any day!
Wee ones: How many eggs are in a “dozen”? If you have a 1-dozen egg carton, count to find out!
Little kids: Raw eggs wobble when they spin, but hardboiled eggs don’t. If you have 4 wobbly eggs and the same number of non-wobbly eggs, how many do you have in total? Bonus: If you stack 10 pounds of books and your 10-pound cat on top of an egg, how many pounds is your egg holding?
Big kids: If you sleep 10 hours and it’s dark tonight for 12 hours, but you sleep 1 hour past sunrise, how many hours of dark will you be awake? Bonus: If you balance an egg at 12:57 pm your time, and it stands for an hour and 15 minutes, when does the egg finally tip over?
Wee ones: A dozen equals 12 eggs.
Little kids: 8 eggs. Bonus: 20 pounds.
Big kids: 3 hours, since you sleep just 9 hours of dark. Bonus: At 2:12 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.