As the excerpt states, “One of the most often-cited reasons for the STEM achievement gap is the lack of skilled and trained STEM teachers.” Findings indicate that a large percentage of K-12 teachers are under-qualified in STEM disciplines. As a result, students are not getting the education they need in order to be competitive in these fields. In many cases, teachers are also contending with poor workplace conditions, lack of funding, and lack of support from peers and school leadership. This report discusses what teachers, administrators, educational leaders and interested citizens can do to improve teacher retention by encouraging and improving opportunities for collaboration, support, respect, openness, and commitment to student achievement and professional development within schools. It presents original findings from a longitudinal study of public school science and math teachers in California participating in Professional Learning Communities (PLCs).