Recent federal policy initiatives are aimed at improving disadvantaged students' access to effective teaching. These efforts, including Race to the Top and the Teacher Incentive Fund, arise from concerns that disadvantaged students are taught by less effective teachers. A growing body of research uses value-added analysis to measure teacher effectiveness and then examine whether disadvantaged students receive less effective teaching. Value added measures a teacher's contribution to student learning, accounting for the student's previous achievement level and background characteristics. Given the importance of teachers in improving student achievement and concerns about unequal access to effective teachers (Jerald et al. 2009; Brown and Haycock 2011), more evidence on access to effective teaching is needed. To address this need, the U.S. Department of Education's Institute of Education Sciences contracted with Mathematica Policy Research to examine access to effective teaching in a diverse set of school districts nationwide over a five-year period from the 2008-2009 to the 2012-2013 school years. This report addresses access to effective teaching in grades 4 through 8 for the first three years of the study (2008-2009 through 2011).