Supporting youths' STEM dispositions takes an entire community of adults, yet we must understand the dispositions that adults bring to such community efforts, ways they influence youths' learning and are shaped by the community. In this paper, we examine a sociotechnical system called Science Everywhere, which invited the broader community to interact with science learning experiences youths shared across home, school, and community settings. Integrating frameworks for disposition and asset-based community development, we present a case study of four focal adults within Science Everywhere embedded in one neighborhood. We make the case for a relational perspective of disposition development that leverages community members' science and relational assets to foster dynamic, community-specific learning opportunities for youths, particularly those from resource-constrained communities.