Water in the Earth System (WES) is a distance-learning course for precollege teachers partially delivered via the Internet, developed and coordinated by the American Meteorological Society's education program, and funded by the National Science Foundation. Central to WES is an innovative paradigm in which the global water cycle is a vehicle to explore Earth system science with special emphasis on (1) the flow of water mass and energy, (2) interactions among the hydrosphere, cryosphere, atmosphere, lithosphere, and biosphere, and (3) human/societal impacts on and responses to those interactions. WES is aligned with the goals of the National Science Education Standards. And the design of WES course components (i.e., investigations, homepage, customized text) models a science content-rich and highly motivational teacher enhancement experience.

The initial year of WES operation (1999-2000) was devoted to developing and critically reviewing course components and selecting and training 35 Local Implementation Team (LIT) leaders. WES LIT leaders (and many members) were formed from a cadre of teachers who had participated in Project ATMOSPHERE, DataStreme Atmosphere, or the Maury Project. These master teachers from around the nation attended three summer workshops (Annapolis, MD in 2000, Madison, WI in 2001, and State College, PA in 2002) where they received instruction on selected concepts in meteorology, oceanography, and hydrology. Pilot offering of WES took place in Spring 2001 with WES LIT members taking the course and providing ongoing constructive feedback on course components and operation. This feedback was the basis of course revisions made prior to national implementation in Fall of 2001.

Through the Fall of 2002, more than 900 teachers nationwide have successfully completed WES. The considerable feedback obtained from those teachers and WES LITs indicates that WES works and is achieving its stated objectives. Participant's written evaluations of the course are overwhelmingly positive. WES alumni exhibit significant growth in their understanding of water-related aspects of Earth system science, have gained valuable experience in working with online environmental data, and report meaningful applications of course resources in their classrooms and schools as they assume their roles as WES resource teachers.