This article describes an NSF RET program’s implementation, evaluation, and outcomes focused on curriculum development through a team-based approach over consecutive years for middle and high school science teachers. During a summer program, teachers designed lessons to engage students in scientific research or engineering design that align with National Generation Science Standards while incorporating themes from the Center for Power Optimization of Electro-Thermal Systems (POETS) areas of research. Interviews and focus groups were used to collect data on teacher experiences, impact on pedagogy, the influence of COVID-19, and perceived benefits for students. This article reports on the findings with teachers over three years. Teachers reported (1) positive collaboration between peers and researchers, (2) increased skill development and creativity, (3) shifting to a student-centered emphasis, and (4) fostering students’ ‘thinking and being’ like scientists. Implications for RET programs and future research are discussed in connection with the findings.