Shifting demographics show America rapidly diversifying, yet research indicates that an alarming number of diverse students continue to struggle to meet learning outcomes of collegiate mathematics curriculum. Consequently, recruitment and retention of diverse students in STEM majors is a pervasive issue. Using a sociocultural perspective, this study examined the effect of two pedagogies (traditional instruction and cooperative learning) in a diverse College Algebra course on enhancing students' mathematics self-efficacy. Particular attention was paid to investigating the role interaction and discourse play in facilitating learning, improving conceptual understanding, and empowering students to engage in future self-initiated communal learning. The goal was to develop an effective classroom model that cultivates advancement in knowledge and enculturation into the STEM community, culminating in a higher retention rate of diverse students in STEM disciplines. Results indicate that a hybrid model encompassing both traditional instruction and cooperative learning successfully enhances students' self-efficacy. [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.]