This Research Brief investigated differences among schools in the initial student achievement and annual rates of ELA growth in middle grades using a variety of student and school demographic characteristics. It found a statistically significant difference in the initial ELA achievement but not in the annual rates of ELA growth between students in K-8 Centers vs. those in traditional middle schools and between students in traditional vs. charter schools. In addition, the Brief identified schools with relatively high rates of annual ELA growth. These schools may have found some pedagogical approaches that resulted in higher rates of ELA learning. These approaches may deserve a deeper look by the District curriculum staff.