This study analyzes four cohorts of 5th grade students in the Baltimore City Public School System (BCPSS) from 2002-03, 2003-04, 2004-05, and 2005-06. The primary group of interest is 5th grade students at the BCPSS KIPP school for each of these cohort years. We then use data available from BCPSS to describe and trace the trajectory of these KIPP students over time, compared to 5th grade cohort groups from the feeder KIPP schools in each cohort year (defined as those 4th graders the prior year who were promoted to 5th grade as each KIPP cohort began 5th grade).