Fun classroom activity to have the students find pi in a variety of circular objects. Marginal error happens frequently so have student who finds the most precise pi number a winner!
Teacher finds a variety of circular objects and breaks students in groups of 3. Have students measure the circumference around the circle on string and measure the string using a ruler. Use the string also to find the diameter. When both numbers are found, divide the circumference by the diameter. If the student gets 3.14159.... then that student found pi!!