Radioactive Decay: A Sweet Simulation
http://www.sciencenetlinks.com/lessons.cfm?DocID=178

Science NetLinks, American Association for the Advancement of Science


Students will enjoy using M and M’s to simulate radioactive decay in this activity from Science NetLinks. This lab demonstrates that the rates of decay of unstable nuclei can be measured, that the exact time that a certain nucleus will decay cannot be predicted, and that it takes a very large number of nuclei to find the rate of decay.

This resource is referenced here:
Subject: Geoscience:Geology:Geochemistry:Radioisotopes
Resource Type: Scientific Resources:Overview/Reference Work, Activities
Theme: Teach the Earth:Course Topics:Geochemistry