Among the 50 states, 44 use free and reduced-price lunch enrollment to identify low-income students. These data are also commonly used to allocate federal, state, and local funding to schools serving low-income children. School and district poverty rates, as determined by free and reduced-price lunch enrollment, additionally feature prominently in social science research, school-funding lawsuits, state laws and regulations, and philanthropic investment. However a close look shows that free and reduced-price meal designations in the National School Lunch Program are grossly inaccurate indicators of family income. While it has been understood for some time that school lunch enrollment as a poverty indicator is blunt and prone to error, the magnitude of the problem has not yet been fully appreciated. In exploring the rules, features, and processes of the National School Lunch Program, the authors find that the program's design, incentives, and lack of income-verification enforcement likely contribute to the oversubscription. These findings raise important questions about the administration of a program that supports the nutrition of American schoolchildren as well as key datasets driving policy and funding decisions across the country.