Fill it out and turn it in: that's the message thousands of school districts send parents each year when they offer applications for the federal government's National School Lunch Program (NSLP). And each year, millions of parents comply. But new data suggest that the process for verifying eligibility for the program is fundamentally broken and that taxpayers may be picking up the tab for participation by ineligible families. The NSLP, which is administered by the U.S. Department of Agriculture (USDA) at an annual cost of $8 billion, serves 31 million American children each day. The program's goal is to help low-income students succeed in public and private school classrooms by ensuring they have adequate nutrition, a mission that is compromised if substantial funds are being spent on ineligible families or the program fails to reach the neediest students. Determining the extent of program fraud and error is important, as the entitlement is associated with other streams of federal, state, and local taxpayer dollars. Eligibility data are widely used as a proxies for poverty rates, thereby influencing funding for myriad government programs and informing both school district policies and policy research. The political climate in Washington makes it doubtful Congress will revise the verification structure of the NSLP in the near future. The entitlement has a long history of partisan strife and is generally recognized as a political hot potato. To make matters more complicated, the program is the product of a political alliance between agriculture Republicans and metropolitan-area liberals, which means that critics are few and far between. But the possibility of waste and fraud warrants a closer look from elected officials. Because the NSLP is the nation's second-largest food entitlement, unqualified families could be costing taxpayers billions each year. The challenge is balancing program integrity with income verification policies that might have a chilling effect on eligible families. At the very least, the author contends, Congress should establish clearer guidelines for school districts to investigate suspected fraud and explore alternative income-documentation methods that would provide greater reliability for program data. Given the amount of taxpayer dollars devoted to school lunch, and the range of policies and research based on the program, lawmakers can't afford to do nothing. (Contains 1 figure.)