The purpose of this case study was to examine how one high-performing California TK-6th grade public elementary school had committed to the development of 21st century skills. Specifically, this study sought to identify the practices and structures at Utopia Elementary that allowed students of low socio-economic status and students with an identified learning disability to be successful. Utopia Elementary in the Sunshine School District voluntarily participated and had met the criteria. There were 4 school visits, 9 staff members who participated in semi-structured interviews, 8 students who participated in a focus group, and extensive analysis of artifacts from the 2019-2023 academic years. The collection of qualitative and quantitative data provided a comprehensive analysis of the effective practices at Utopia Elementary other educators can implement in an elementary school setting to develop 21st century skills in marginalized groups. Using the P21 Framework (P21), Wagner's Seven Survival Skills, the Four Keys to College and Career Readiness, and the OECD Learning Compass Framework 2030, the study developed the conceptual framework for the research. The research results discussed the similarities of the conceptual framework, research question findings, and elements from the four 21st century skill development research models. Implications from this study include the importance of a Professional Learning Communities (PLC) in schools to address the teaching and learning of 21st century skills, the importance of student agency in learning, the role of local community partnerships to provide access to positive role models and resources, and extended learning opportunities as a mechanism to develop 21st century skills for students for varying demographic background. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]