The nature and purpose of this study was to examine the self-efficacy of teachers who use an inquiry-based science program to provide authentic experiences within the elementary school setting. It is essential to explore necessary improvements to bring about effective science education. Using a mixed methods study, the researcher conducted interviews with elementary teachers from five elementary schools within the same school district. The interviews focused on the teachers' experiences with inquiry-based science and their perceptions of quality science instruction. The Teachers' Sense of Efficacy Scale was used to collect quantitative data regarding the teachers' perception of instructional practice and student engagement. The study revealed that limited science content knowledge, inadequate professional development, and a low sense of self-efficacy have a substantial effect on teacher outcomes, instructional planning, and ability to motivate students to participate in inquiry-based learning. It will take a collective effort from administrators, teachers, parents, and students to discover ways to improve elementary science education. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]