The purpose of this correlational study was to examine the relationship among the mathematical self-efficacies, mathematical teaching self-efficacies, and instructional practices of elementary teachers. This study was also designed to determine how these variables influence an individual teacher's QDI in relation to MCT2 math scores in grades 3-5. The study included 117 third, fourth, and fifth grade elementary teachers who taught mathematics during the 2012-2013 school year. These teachers completed the Mathematics Teaching and Mathematics Self-Efficacy (MTMSE) survey and the Patterns of Adaptive Learning Scales (PALS) survey. A descriptive analysis was conducted on the data collected. The results of the study indicated that teachers are most confident teaching the numbers and operations strand of the NCTM 2000 standards for mathematical content. However, teachers indicated an overall confidence in their ability to teach all mathematical topics related to the NCTM 2000 standards. Teachers agreed that they should incorporate instructional practices that stress the importance of students working hard and that strategies should be fun and keep students from being bored in the classroom. Teachers also agreed that students should be recognized for individual progress and that instruction should be differentiated based on students' needs. A multiple regression was also used to analyze the data. The results of the statistical analysis indicated that there is no statistically significant relationship between MCT2 math QDI and mathematics self-efficacy problems, mathematics teaching self-efficacy, mathematics self-efficacy tasks, and mathematics content teaching self-efficacy. The results also indicated that there is no statistically significant relationship between MCT2 math QDI and mastery goal structure for students, performance goal structure for students, mastery approaches to instruction, and performance approaches to instruction. The research indicated that self-efficacy and instructional practices may not be good predictors of an individual teacher's QDI. Therefore, self-efficacy may not correspond to a teacher's actual ability. Teachers may think that they are better or worse teachers than they actually are, and this factor could affect QDI. When analyzing a teacher's QDI, practitioners should take into consideration other factors such as class size, student ability, and student attendance. [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.]