This dissertation presents the findings of a qualitative improvement science study aimed at identifying an effective professional development structure to enhance teacher efficacy in the context of post-COVID-19 education. The study's approach was guided by improvement science, a systematic exploration of the problem, facilitated by a driver diagram, which led to the identification of three potential change ideas. Among these ideas, the second change idea involved the design of a school master schedule, which provided teachers with two planning periods, the initial step towards achieving the research goal. To operationalize this change, Plan-Do-Study-Act (PDSA) cycles were employed iteratively to develop a tailored master schedule. Following a series of five PDSA cycles, a comprehensive master schedule was established, featuring two designated planning periods for teachers. One of these planning periods was allocated for the implementation of a revised Professional Learning Community (PLC) process, referred to as ACTS (Academic Collaboration Team Sessions) meetings. After five weeks of schedule implementation, data was collected from sixteen participating teachers through open-ended surveys and focus groups. The analysis of this data revealed a significant improvement in teacher efficacy attributed to the additional time integrated into the master schedule. These findings offer practical implications for educational institutions seeking to optimize teacher effectiveness and student outcomes in a changing educational environment. [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.]