This is a quick experiment dealing with the measurement of different circular objects. The directions state that you measure four different objects and put the findings in the data table. The last box is circumference divided by diameter so students will realize that the answer is always pi. I usually bring in CD's, soup cans, jars and so forth for my objects. Also, depending on the size of the objects I just determine as a class whether they are to use centimeters or inches. This would be a great introduction for the area and circumference of circles. I usually have the students work with table groups or partners.