Federal incentives and requirements under the Obama administration spurred states to adopt major reforms to their teacher evaluation systems. We examine the effects of these reforms on student achievement and attainment at a national scale by exploiting their staggered implementation across states. We find precisely estimated null effects, on average, that rule out impacts as small as 0.017 standard deviations for achievement and 1.2 percentage points for high school graduation and college enrollment. We highlight five factors that likely limited the efficacy of teacher evaluation at scale: political opposition, decentralization, capacity constraints, limited generalizability, and the absence of compensating wages.