The level of philanthropic giving to K-12 education in the U.S. is at an all-time high, yet there are instances in which large amounts of money bestowed seem to have vanished into the system without leaving lasting footprints or a meaningful transformation. The aim of this guide is to provide practical advice for philanthropists who are tired of the status quo and want to have their donations make a difference for all children. The guide begins with an overview of American education today. Chapter one can be considered as a primer on what is and is not working by way of policy-driven reform and why private intervention is needed. In chapter two, theories of change embraced by education reformers are discussed, and explanations are given on why some theories work better than others. Chapter three details issues that every reform-minded philanthropist should ask him or herself before writing a check. Some philanthropists are profiled in chapter four to demonstrate how theories of change work in practice. Chapter five focuses on the authors' own work and insights. Chapter six suggests strategies for advancing education reform goals. (Contains 26 references.) (RT)