In America it’s Labor Day, when we celebrate American workers. To many it also marks the end of summer: closing the swimming pool, wearing shoes again, and starting school. But all of this is pretty unscientific. For one thing, Labor Day falls on the first Monday of September, which could be any of the first 7 days of the month. Since the number of days in a year (365) isn’t divisible by 7, each year the dates move to the next day of the week. Whatever day of the week your birthday is, it will be one day later in the week the next year. So next year Sept. 1 will be on a Tuesday, and August 31 can’t be Labor Day, so suddenly Labor Day happens really late. Meanwhile, summer doesn’t end until the 1st day of fall, which can start on either Sept. 22 or 23; it’s September 23 this year. So the number of summer days in school changes a lot from year to year. All together, it’s best just to find out from school which days you’re supposed to show up! Figuring it all out takes a little labor after all.
Wee ones: Which happens later, September 1 or September 23?
Little kids: If Sept. 1 is on Monday this year, and next year it moves 1 day later in the week, what day will Sept. 1 be next year? Bonus: If Labor Day has to be the first Monday in September, on what date will Labor Day land next year?
Big kids: If Sept. 22 is the last day of summer this year, how many days of school land in summer for kids who start Tues., Sept. 2? (Assume school on all weekdays and no weekend days.) Bonus: What will that number be in 2016 if you start the day after Labor Day?! Remember, Labor Day moves, and 2016 has a leap day, which pushes dates 2 days down…and fall starts on Sept. 22 that year.
Wee ones: September 23.
Little kids: On Tuesday. Bonus: Since Sept. 1 will be a Tuesday, and Sept. 2 a Wednesday…the first Monday will be Sept. 7.
Big kids: 15 days: 4 the first week, 5 each the weeks of Sept. 8 and Sept. 15, and then Monday Sept 22. Bonus: In 2015 Labor Day will land on Sept 7, then Sept. 7 jumps two days later to Weds. in the week for 2016, so Labor Day 2016 will be Monday, Sept. 5. That leaves 4 days the first week, then 5 the week of Sept 12, then just 3 the following week – Sept. 19, 20 and 21 – for a total of 12 days.
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.