The Exploratorium, in collaboration with the Boys and Girls Club Columbia Park (BGC) in the Mission District of San Francisco, is implementing a two-year exploratory project designed to support informal education in science, technology, engineering, and mathematics (STEM) within underserved Latino communities. Building off of and expanding on non-STEM-related efforts in a few major U.S. cities and Europe, the Exploratorium, BGC, and residents of the District will engage in a STEM exhibit and program co-development process that will physically convert metered parking spaces in front of the Club into transformative public places called "parklets." The BGC parklet will feature interactive, bilingual science and technology exhibits, programs and events targeting audiences including youth ages 8 - 17 and intergenerational families and groups primarily in the Mission District and users of the BGC. Parklet exhibits and programs will focus on STEM content related to "Observing the Urban Environment," with a focus on community sustainability. The project explores one approach to working with and engaging the public in their everyday environment with relevant STEM learning experiences. The development and evaluation processes are being positioned as a model for possible expansion throughout the city and to other cities.