This report is a follow-up to "Gaining Ground in the Middle Grades" (Williams, Kirst, Haertel, et al., 2010). That study specified a comprehensive set of actionable practices that differentiated higher academic achievement among 303 middle grades schools in California. In doing so, the study provided a compelling and coherent account of middle grades schools that are achieving better student outcomes than their peer schools serving similar students. This follow-up analysis provides a different, more in-depth look at middle grades mathematics practices and policies. Appendices include: (1) Further data on Algebra I placement; and (2) The credentials of middle grades mathematics teachers differ depending on school grade configuration and teachers' grade levels. A technical appendix is included. (Contains 50 figures and 53 footnotes.) [For the related report, "Gaining Ground in the Middle Grades: Why Some Schools Do Better. A Large-Scale Study of Middle Grades Practices and Student Outcomes. Initial Research Report", see ED508673.]