This Noyce Track 4 project aims to serve the national need of examining the effectiveness and retention of K-12 STEM teachers in high-need school districts. This project will focus on the persistence and the effective instructional practices of mathematics teachers. Currently, many schools have high teacher turnover rates, and many teachers experience significant challenges during their first few years of teaching. To address this problem, this research project will collect audio and video data to learn about the experiences and practices of mathematics teachers in their first five years of teaching in high-need school districts. The proposed project hopes to understand the different forces that support teachers during their first five years of teaching, how they make decisions about instruction, what opportunities they have to continue learning, and what their aspirations are for the future. In this way the project seeks to generate knowledge that is useful for retaining effective mathematics teachers, including those who serve rural communities. This project at the University of Arizona includes partnerships with Northern Arizona University, University of North Carolina at Charlotte, and numerous local educational agencies. Project goals include exploratory studies that address both STEM teacher effectiveness and retention in high-need LEAs. The research project will use evidence-based principles in studying the effectiveness and retention of STEM teachers. This longitu