PROJECT SUMMARY/ABSTRACT The Science & Health Education Partnership (SEP) at the University of California, San Francisco (UCSF) proposes Constructing a Community of Teen Health Science Leaders (THSL). THSL is designed as a leadership opportunity that offers a roadmap for its teen participants to recognize themselves as “science leaders.” The teen participants, from backgrounds underrepresented in the sciences, will work closely with UCSF faculty to understand the NIH-funded research that informs teen health recommendations. Through these collaborations, the students will identify health issues that impact their community and plan how to share this information at a one-day Health Summit for their peers. Design of the Health Summit (its speakers, session styles, and interactive activities) will be informed by participants’ knowledge of their community and how best to inspire engagement among their peers. The Health Summit will also give these students the opportunity to be recognized as science leaders among their peers. We believe that this leadership opportunity will engender a sense of belonging in science that will encourage the student participants to ultimately pursue STEM careers. The specific aims for this project are to: 1) Develop a community of Teen Health Science Leaders; 2) Support Teen Leaders as they organize and lead the annual Teen Health Summit; 3) In collaboration with learning researchers, develop a validated instrument to measure “Belonging in Science,” and test the impact of THSL on students’ sense of belonging; and, 4) Publish the results of the learning research in peer-reviewed journals to inform and advance the science education community’s understanding of student belonging in science. In order to study the program’s impact on belonging in science, THSL incorporates two levels of engagement among the Teen Leaders. Over the life of the project, 80 students will serve as Junior Leaders, with 15 of these students selected to rejoin the program in subsequent years as Senior Leaders. The Belonging in Science survey instrument will compare the responses of all THSL Teen Leaders to the control group of Health Summit student attendees (600 over the life of the grant). Lessons on healthy behaviors from the Health Summit will be further amplified by sharing teen-crafted health messaging via social media and by presenting interactive activities from the Health Summit at the Bay Area Science Festival. Combined over the life of the grant, we anticipate reaching more than 52,000 additional people with public health messaging designed and facilitated by teens.