Background/Context: Teacher collaboration, instructional practices, and efficacy are linked in various ways in the literature. For example, in schools where teachers reported greater use of differentiated instruction, team collaboration and culture were reportedly higher (Smit & Humpert, 2012). Further, teachers' instructional mastery…

The present study seeks to determine how exposure to pre-differentiated and enriched curricula incorporating educative curriculum materials affects students' achievement as well as teacher and administrator responses to the intervention. A 2-year multi-site cluster randomized control trial study recruited a national sample of 4,530 grade 3…