Abstract
This thesis explores the influence of professional learning on teacher understanding of the Multi-tiered System of Supports (MTSS), particularly focusing on literacy differentiation and intervention. Through two 50-minute professional learning sessions utilizing the jigsaw method, participants engage in an analysis of adapted texts across critical areas of MTSS implementation. Data collected through surveys, observation protocols, and a practices and challenges chart reveal a generally vague comprehension of MTSS among participants with nominal improvement post treatment. Implementation barriers include time constraints, external control, and limited use of evidence-based materials. The findings emphasize the necessity for sustained professional development, integrating theory and practice effectively, to enhance MTSS implementation and ultimately improve student achievement.