The success of all students in schools, including students with learning differences, is contingent on how schools operationalize universally designed instruction, positive behavior support, and data-based decision-making for individualized and group-level interventions. When schools have fully functional multi-tiered systems of support (MTSS) that center equity and focus necessary attention on academic conditions, student behavior, and social-emotional learning conditions, students are more likely to receive the instruction and interventions they need. Further, there is evidence of improvements in student outcomes, particularly those related to behavior, when MTSS is implemented effectively. To address the need for effective MTSS implementation, WestEd engaged in a research and technical assistance partnership in which WestEd subject matter experts provided guidance on designing and implementing effective MTSS. WestEd researchers simultaneously studied the short-, mid-, and long-term effects of these efforts on student outcomes. This interim report provides initial analyses of student-level impacts in one of the two school districts involved in this project.