This article identifies two presuppositions underlying No Child Left Behind's (NCLB) system of adequate yearly progress. The first is that each state must bring 100% of its students up to proficiency on state tests by the 2013-14 school year. The second is that each student's test score must effectively be treated by the state as if his or her school were 100% responsible for that score. The article demonstrates that these two 100% presuppositions are unsupportable and then explores the NCLB rules in the context of the Fourteenth Amendment's Due Process Clause, which prohibits the government from arbitrary exercises of power.