Common Core – Grade 7 (7.G.4)
Students, for the most part, seem to have very little trouble finding the area of basic quadrilaterals. Then we throw in a Greek symbol and ask them to find the area of a circle and it gets a little more tricky. Introduction to Area of a Circle, shows students the connection between finding the area of a parallelogram and finding the area of a circle.
A brief animation on page 3, shows how sectors of a circle can be transformed into the shape of a parallelogram. The activity then proceeds to walk students through the concept of using the formula for finding the area of a parallelogram and the characteristics of a circle that they already know to find the area of a circle.
As students progress through this activity they are provided with many opportunities to practice finding the area of a circle. This activity provides an introduction to this concept. For a follow up to this activity, check out Area of Circles.