The Early College program has a proven track record of academic success as noted through graduation rates, growth data, performance grades, and higher than statewide average test score averages. Research on the success of Early College methods is limited. This study analyzed the effects of a heterogeneously grouped Honors Math 1 classroom on students' mathematics self-concept and academic achievement. Complex Instruction Theory, Systems Theory, and Self-Efficacy Theory provided a framework that encapsulated the experiences of students, staff, and administrators in the Early College environment. The study utilized a convergent mixed methods design where qualitative and quantitative data was gathered separately then analyzed concurrently. The data was organized through the lens of a case study to understand the phenomenon that was occurring at the STEM Institute, a specific Early College in the piedmont of North Carolina. Participants included three students, one Honors Math 1 teacher, the principal, and the assistant principal. The researcher gathered survey results, interviews, and documents. Numerical pre and post-test scores were also analyzed for the fall of every school year from 2016 to 2022 using a paired samples t-test. Findings concluded that school culture, paths to learning, and organizational structures significantly impacted student self-concept and academic achievement. These findings provide stakeholders with a fundamental understanding of the Early College program, information regarding detracking and cohorting as a method of school culture, and the possibility of replication of the program outside of the program studied. [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.]