math, statistics, pi, pi day, pi day activities, science, experiment, fractions, multiplication, division, algebra, algebraic formula, rearranging an algebraic formula, measuring, metric measurements, graphs, bar graphs, proportions, percentages, estimating, estimation, estimating the value of pi, value of pi, Buffon's Needle, Count of Buffon, comte de Buffon, mathematics activity, biography, high school The activities in Mathematics Activity: Estimating the Value of Pi - Using the Buffon's Nee