Radon is a naturally occurring radioactive gas in ambient air that is estimated to cause thousands of deaths from lung cancer each year. This report outlines ways in which to ameliorate the presence of radon in schools buildings. The first section is a general introduction for those who need background information on the indoor radon problem and the techniques currently being studied and applied for radon prevention. The level of detail is aimed at developing the reader's understanding of underlying principles and might best be used by school officials or by architects and engineers who need a basic introduction. Instructions and guidelines for radon amelioration are provided in section two, which contains more technical details and may best be used by the architects, engineers, and builders responsible for specific construction details. When building in an area with the potential for elevated radon levels, architects and engineers should use a combination of radon prevention construction techniques. It is also recommended that when constructing a school in radon-prone areas the builder should install an active soil depressurization system; pressurize the building using the heating, ventilating, and air conditioning system; and seal major radon entry routes. Three appendixes provide a case study in the application of radon prevention design measures, a list of references, and a list of EPA regional offices and contacts. Includes an addendum highlighting new field-verified technologies, specifically a method for increasing pressure field extension by modifying subslab walls and improved suction pits. (Contains 19 line drawings and 3 tables.) (RJM)