In my short experience in teaching, most of my students are content to just memorize the formulas without ever knowing were and how they were acquired. These activity and discussions will allow students to learn how pi was discovered, and how they can use pi to find the circumference and area of circles. Till this point most of the numbers students have been working with have been rational numbers. The concept of a decimal that keeps going and going is difficult for them to understand. In this unit the students will explore why we shorten pi to 3.14, and understand that 3.14 is not equal to pi but approximately pi.