No matter where in the world you are or how you write the date today (15/08 or 08/15), August 15 2017 is Pythagorean Theorem Day! 8² + 15² =17² OR  15² + 8² = 17² This doesn’t happen every year so it’s mathematically special!

Pythagorean Theorem Day or Pythagoras’ Theorem Day can be celebrated today, 08/15/2017 because the sum of the squares of the first two digits (8 & 15) equal the square of the last digit in the date (17).

The Mathletics Dictionary tell us that Pythagoras was a Greek philosopher and mathematician. He was born around 569 BC and died around 475 BC. He is most well-known for his theorem we celebrate today; c² = a² + b²



Ways to celebrate Pythagorean Theorem Day:

1. Since it’s also considered right triangle day, take a walk and identify right triangles all around you.
2. Make fun right triangle sandwich snacks or cut other food items into right triangles.
3. Practice with tangrams.
4. With parent support, build something with wood that requires right triangles.


Pythagorean Theorem Mathletics sample activities

1.       Pythagoras Jigsaw Puzzle: Print & cut out or Interact online

2.       Printable Worksheet: (pages 5-8)


When are the next Pythagorean Theorem days?

Have your learners figure it out! Start by giving them the hint that Pythagorean Theorem Day will occur again in 2020 and 2025. You can provide the month to make it a little easier.

  •   December 16, 2020 (12/16/20 or 16/12/20): 12² + 16² = 20²
  •   July 24, 2025 (7/24/25 or 24/7/25): 7² + 24² = 25²


Find out more about the Pythagorean Theorem… with chocolate!