In this study, the authors ask what classroom practices, if any, differentiate teachers with high impact on student achievement in middle school English Language Arts from those with lower impact. The study further explores the extent to which value-added measures signal differences in instructional quality. Even with the small sample used in the analysis, there is evidence that high value-added teachers have a different profile of instructional practices than do low value-added teachers. Teachers in the top quartile as measured by value-added scores score higher than second-quartile teachers on all 16 elements of instruction that were measured. The differences are statistically significant for a subset of practices including explicit strategy instruction.