*This post was written by shopkeeper K-8 Math Paths.*

Are you ready for Pi Day, March 14th? Here’s a way to give more meaning to that special number close to 3.14.

Many students are confused by the formulas for circumference and area of a circle. In CCSS, circle relationships and formulas are to be taught in Grade 7, standard 7.G.4. To help my students with circumference and area, I’ve developed a visual approach.

First consider the circumference or distance around a circle. I ask leading questions to help students estimate the circumference as a multiple of the length of the diameter, based on these diagrams.

For area, I help students relate the area of a circle to the square of the radius.

I help students see that when the diameter of a circle is 1, the circumference is pi! And, if the radius is 1, the area is pi! If students *visualize *the relationships between parts of circle, they are more likely to develop an understanding of the formulas.

Happy Pi Day!