The research study focuses on characterizing and measuring growth in STEM teachers' assessment practices as a major driver of teacher effectiveness. The project will compare differences in the assessment practices of Noyce-program teachers to other K-12 STEM teachers from the same area who participated in different training programs. The research employs both qualitative and quantitative methods, in an interaction analysis framework. The project aims to increase knowledge about STEM teacher effectiveness by how teacher effectiveness may relate to teachers measure their students' understanding. The evaluation focuses on supporting the rigor of the project's own research study, addressing issues of design, instrumentation, sampling, data collection, analysis, and interpretation.