This technical brief examines whether, after two years of implementation, schools in Massachusetts using quarterly benchmark exams aligned with state standards in middle school mathematics showed greater gains in student achievement than those not doing so. A quasi-experimental design, using covariate matching and comparative interrupted time-series techniques, was used to assess school differences in changes in mathematics performance between program and comparison schools. Following up on an earlier report with just one year of post-implementation data, the study found no significant differences between schools using this practice and those not doing so after two years. The brief summarizes findings from a follow-up study to the Issues & Answers report, "Measuring How Benchmark Assessments Affect Student Achievement. REL 2007-No. 039" [ED499792]. The follow-up study adds another year of post-implementation data to examine the impact of benchmark assessments on grade 8 mathematics achievement, using the same data sources, methods, and reporting as the original study. The study examines whether, after two years of implementation, schools in Massachusetts using quarterly benchmark exams aligned with state standards in middle school mathematics showed greater gains in student achievement than those not doing so. A quasi-experimental design, using covariate matching and comparative interrupted time-series techniques, was used to assess differences in changes in mathematics performance between program and comparison schools. The follow-up study finds no significant differences between schools using this practice and those not doing so after two years. Limitations include the lack of data on what benchmark assessment practices comparison schools may be using, having only 22 treatment and 44 comparison schools, and having only two years of post-implementation data--perhaps still too few to observe an impact from the intervention. Details on the analysis are appended. (Contains 7 tables and 1 figure.) [This report was prepared for the Institute of Education Sciences by Regional Educational Laboratory Northeast and Islands administered by Education Development Center, Inc.]