As social, racial, and environmental justice topics dominate national conversations, STEM teachers must provide learning opportunities that support students to make sense of these problems and co-construct hope for their futures (Calabrese-Barton et al., 2020; Ojala, 2012). Thinking about how teachers can begin to transform their classrooms into places where discussions about inequity, power, environmental justice, and STEM are commonplace, requires the design of innovative opportunities for youth to engage critically with STEM content and acquire skills to transform their current realities and hoped-for future (e.g., Calabrese Barton et al., 2020; Ladson-Billings, 1995; Morales-Doyle, 2017; Rubel, 2017). This dissertation is framed around a potential innovative STEM classroom discourse routine, "Community Science Data Talks" (CSDTs). The purpose of this study was to examine the potential of CDSTs as a tool for teachers and students to co-construct the learning environment to discuss and learn about local environmental justice issues. The main objective of this study was to investigate if CSDTs could over time stretch teachers' visions of classroom learning and expand students' experiences with local science. This design-based convergent parallel mixed methods case study compares two classrooms in different contexts (i.e., privileged and underserved) to understand "what is possible" when teachers and students engage in CSDTs. The findings indicate that students across contexts became more proficient in STEM disciplinary practices, had a transformative experiences (e.g., Pugh, 2011), and constructed hope for their futures (e.g., Ojala, 2012). Students constructed hope through different pathways depending on their context. Additionally, the small-scale practice of CSDTs supported teachers in both contexts to experience moments of bearing witness that stretched their pedagogical visions in justice-oriented ways (Hansen, 2017). Overall, these findings indicate that CSDTs are a small-scale justice-centered STEM routine that can provide access for teachers and students to begin working in more transformative ways together (Calabrese Barton et al., 2020; Morales-Doyle, 2017). [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]