Precipitation is the most visible, the most talked about, and the most easily measured component of the water cycle. It also, because of its variability, has the most direct impact on all of our lives and livelihoods. For five years now, the Community Collaborative Rain and Hail Study (CoCo RaHS) has involved hundreds of students and adults over a wide range of ages and backgrounds in the study of local precipitation patterns in northern Colorado. Students from the elementary grades on into college continue to team with adults and senior citizens in accurately measuring and mapping the rainfall, snowfall and hail from each storm using accurate but low-cost instrumentation. What began in 1998 as a local project in Fort Collins, Colorado, following a devastating but highly localized 1997 flash flood, has now grown to encompass 20 counties of northeastern Colorado. CoCo RaHS continues to expand each year. Sponsoring organizations such as the National Weather Service, the U.S. Department of Agriculture, local municipalities, schools and businesses have already donated hundreds of high-capacity rain gauges to help the project. More than two dozen organizations are currently helping out, and as of June 2002 over 1100 volunteers including students from at least 60 different schools have been trained and equipped. This number may increase significantly in the next few years. Two dozen high school and college students have had their first job in scientific research thanks to sponsor support. Only with the help of the Internet can so many volunteers participate along side a variety of scientists. The main output of this project is very simple -- maps that show accurate precipitation patterns at the community level where the remarkable variations and extremes in precipitation can be clearly shown and documented and where participants can immediately see the results of their work and the effects within their community. Organizations willingly sponsor this project because they can instantly access precipitation patterns from their own communities. Students and teachers learn how storms behave and then have a firm starting point for appreciating other aspects of the hydrologic cycle -- runoff, soil moisture, plant growth, evaporation, transpiration. It leads to a strong appreciation for the variability within the water cycle and the impacts that has on our world, our community and our lives.