Happy Pi Day! I made this free set for you to try out as a Pi Day activity. You students will be comparing the length of a circle’s diameter to its circumference (which will lead to the discovery of Pi and the circumference formula). It might sound complex but this activity makes it easier to these concepts because it allows for a concrete understanding if diameter, Pi and circumference. It is created for two different sizes of circles; for the 7cm diameter circle and for the 14cm diameter circle. All dimensions are in cm (metric) units. It also contains posters which show the many different ways of representing Pi. It’s a free download that you can access right here from my Teachers pay Teachers collection.