This study identified the relationships among English Language Arts teacher teams, their collaboration in creating formative assessment, and its impact on the academic achievement of middle school students. The setting of this study was two urban private Nursery through Grade 8 elementary schools in 1 New York City district. The design for this study was a mixed-method research design, which gathered both quantitative as well as qualitative data to answer the research questions. The research included observations, interviews, small samples of lesson plans, and standard assessment tools (t-test). The observations took place in 2 different 6th grade English Language Arts classrooms, as well as observations of 1 school's teacher team meeting. The data gathered, in addition to the observations, were pre- and post-English Language Arts test from both classes. The results did not support the theory that when teachers work collaboratively in teacher teams, that there is a positive impact on their students' academic performance.