In this paper, we present a closer look at the student achievement trends in the District of Columbia between 2006-07 and 2012-13. We have three main conclusions. First, we find that overall, math scores in the District have improved. The improvements in reading scores during this time frame, however, were primarily limited to the first year after the PERAA implementation. While almost all student subgroups have experienced test score gains in math, these improvements were higher among the more affluent black and Hispanic students. Second, we find that these observed trends in math scores persist even after controlling for the cross-cohort differences in observed student characteristics. In particular, the estimates indicate that less than 10 percent of the year-to-year improvements in test scores can be attributed to the changing student composition in the District over this time frame. Finally, we show that existing students have also experienced gains in math even though the students who are new to the District's public school system score at higher levels on standardized tests when compared to existing students. Appendix A presents Figure A1--Average NAEP Scores in the District between 2003 and 2013. Appendix B: Subgroup Analysis with Student Covariates contains Tables B1 through B7.