The Massachusetts Department of Elementary and Secondary Education (DESE), like other state education agencies, recognizes that a key lever to turning around low-performing schools is the quality of instruction and thus embeds a schoolwide instructional quality measure into its monitoring process. Massachusetts' schoolwide quality instruction score uses Teachstone's Classroom Assessment Scoring System (CLASS) tool to conduct observations in a sample of classrooms. In state-identified low-performing schools, there were significant positive relationships between schoolwide observation scores and school-level academic growth in both ELA and math, and in ELA academic achievement. Findings are important, because they suggest it is possible for a state to balance capacity limitations and still use an instructional quality measure that is predictive of improved student outcomes.