The No Child Left Behind law mandated the institution of adequate yearly progress (AYP) objectives, on which schools are assigned a pass or fail. Fail status is associated with negative publicity and often sanctions. In this paper, I study the incentives and responses of schools that failed AYP once. Using data from the Wisconsin Department of Public Instruction and regression discontinuity designs, I find evidence in these schools of improvements in high-stakes reading and spillover effects to low-stakes language arts. The patterns are consistent with a focus on marginal students around the high-stakes cutoff, but this improvement did not come at the expense of the ends. Meanwhile, there is little evidence of improvement in high-stakes math or in low-stakes science and social studies. Performance in low-stakes grades suffered, as did performance in weaker subgroups despite their inclusion in AYP computations. While there is no evidence of robust effects in either test participation or graduation, attendance improved in threatened schools where it mattered for AYP. Finally, there is strong evidence in favor of response to incentives: Schools that failed AYP only in reading and/or math subsequently did substantially better in those subject areas. Credibility of threat mattered. AYP-failed schools that faced more competition responded more strongly and also more broadly, robust evidence in favor of improvements in all AYP objectives.