May 2023 - Geometry, Measurement and the Circle!

The circle is an important shape with interesting geometric properties.  It is often one of the first shapes young children learn about as they begin to inquire about the different two-dimensional shapes in their environment.  As children get older, they begin to sort and classify shapes by their properties which leads to some important mathematical discoveries about the circle and a very special number that we call pi.  In the intermediate grades, students learn to identify the properties of circles and develop an understanding of pi and its relation to a circle.

Properties of a Circle

  • Every point on a circle is the same distance away from the centre of the circle.
  • The diameter of a circle is the longest line segment that can be drawn inside the circle
  • The area of a circle can be calculated by multiplying pi by the radius and then by the radius again
  • The circumference of a circle can be calculated by multiplying the diameter by pi.   


Celebrating the Many Global Contributions to Mathematics

Throughout human history, people from many cultures and societies have contributed to the continuously developing understanding of math.  As a part of each monthly newsletter, one of these many significant contributions will be shared in celebration of how diverse ways of knowing have shaped our mathematics today.

Did you know that approximations for Pi have been known for about 4000 years?  Ancient Babylonians used 3.125 in their calculation of areas of circles and later Egyptians used 3.1605.  The symbol that we now use for pi (π) was introduced about 300 years ago. 

To come up with your own approximation of pi, you can find some circles and use a string to measure the circumference (the length of the outer edge) and divide that number by the circle’s diameter.