This handout is a simple discovery activity. Students will calculate the value of pi. They must measure diameter and circumference, and be able to divide them. They will also have to cut and lay out pieces of string, compare lengths and draw conclusions.
I recommend using metric measurement for this activity, in order to simplify the decimal operations involved.
This activity is similar to how I was taught pi. My teacher did the same measurements, and showed us that pi was 3.14 or "three and a little bit." Your students will notice that the three diameter strings that they cut are just a little shorter than the circumference, hence needing the "little bit." Hopefully this will stick with your students, and no one will ever be able to convince them that pi is just 3.