The National Science Foundation's Directorate for Biological Sciences (BIO) will support up to 10 awards annually to enable active research by cohorts of middle school teachers, high school teachers and/or community college faculty. Research Experiences for Teachers Sites (RET Sites; RETS) will be based at institutions of higher learning or other non-profit organizations in the U.S. that conduct educational and research activities. RETS with a focus on Biological Sciences (BIORETS) will include research projects in fields that are supported by the Directorate for Biological Sciences. BIORETS may be based in a single discipline or department or may offer interdisciplinary or multi-department research opportunities with a coherent intellectual theme. An important goal of the program is to increase the participation of underrepresented groups in biological research and those from geographically underrepresented areas in science, technology, engineering, and mathematics (STEM). Proposals are strongly encouraged to involve members of these groups both as participants and as mentors. BIORETS awards are expected to leverage the teachers research experiences for curriculum development, with the goal of enriching their classroom teaching practices and inspiring a broad swath of students to consider higher education and careers in STEM. Teachers supported with NSF funds in BIORETS projects must be U.S. citizens, U.S. nationals, or permanent residents of the United States.