What may be the world’s largest chemistry experiment in history was launched as part of the International Year of Chemistry 2011. The American Chemical Society (ACS) announced it will help support teachers and students who wish to participate in the experiment, Water: A Chemical Solution, by sending volunteers to classrooms that need assistance. In 2011, students worldwide will test their local drinking water sources, as well as local lakes, rivers, streams and other bodies of water, and post their analyses to a global Internet data map. The experiment remains open until Dec. 31. Teachers, scout leaders, and families can register to participate, view the experiments, and enter their results at: http://water.chemistry2011. org. The activities are suitable for students of all ages and require materials commonly found in most science classrooms. Students will conduct four tests to analyze their water resources for characteristics critical to providing clean drinking water, and will learn essential water chemistry practices. They will test the acidity and salinity of their water, and perform simple water treatment and desalinization procedures. Other US organizations helping to coordinate the global experiment include the American Chemical Council (ACC) and the National Academy of Sciences.