Children in households reporting the receipt of free or reduced price school meals through the National School Lunch Program (NSLP) are more likely to have negative health outcomes than eligible nonparticipants. Assessing the causal effects of the program is made difficult, however, by the presence of endogenous selection into the program and systematic misreporting of participation status. Using data from the National Health and Nutrition Examination Survey (NHANES), we extend and apply partial identification methods to account for these two identification problems in a single unifying framework. Similar to a regression discontinuity design, we introduce a new way to conceptualize the monotone instrumental variable (MIV) assumption using eligibility criteria as monotone instruments. Under relatively weak assumptions, we find evidence that receipt of free and reduced price lunches through the NSLP improves the health outcomes of children.