The intent of the No Child Left Behind (NCLB) Act of 2001 is to hold schools accountable for ensuring that all their students achieve mastery in reading and math, with a particular focus on groups that have traditionally been left behind. Under NCLB, states submit accountability plans to the U.S. Department of Education detailing the rules and policies to be used in tracking the adequate yearly progress (AYP) of schools toward these goals. This report examines Minnesota's NCLB accountability system, particularly how its various rules, criteria and practices result in schools either making AYP, or not making AYP. It also gauges how tough Minnesota's system is compared with other states. While most of the states examined apply confidence intervals to measurements of student proficiency rates, Minnesota uses a sliding confidence interval range of 95-99 percent, which makes it easier for Minnesota schools to achieve their targets, with schools that have many subgroups receiving more of a "boost" than schools with fewer targets. Minnesota's minimum subgroup size varies by subgroup: racial, ethnic, and low-income subgroups have lower minimum sizes than subgroups for students with disabilities (SWD) and limited English proficiency (LEP). Because of this, there are fewer subgroups of SWD and LEP students in elementary schools than in generally-larger middle schools, resulting in more elementary schools making AYP. While most states measure school performance by a proficiency rate, Minnesota employs a performance index which gives partial credit to students attaining "partial proficiency." The resultant score for students in Minnesota is always higher than the actual proficiency percentage. Compared to the other 27 states examined, Minnesota places at the high end of the distribution in terms of the number of schools making AYP. The report concludes that although in some respects, Minnesota's NCLB accountability system is working as intended by the legislation, NCLB shortcomings are also evident, and should be considerations for Congress in future reauthorizations of the act. (Contains 10 footnotes, 8 figures and 6 tables.) [For "The Accountability Illusion," see ED504712. For individual state reports, see ED504680-ED504694, ED504700-ED504711 and ED504719.]