Education is a constantly evolving field that requires continuous professional development. While policymakers continue to implement school reforms, many of them depend on teachers' ability to learn and improve instruction to increase student learning. Teachers have a double role in educational reforms by being simultaneously subjects and objects of change. Understanding which components make professional development effective is vital to reasoning about the success of any education reform. This study addresses the problem of preparing teachers to teach new technology-related subjects under the conditions of limited time and resources. Completed work and data gathered during Cybersecurity Professional Development workshops for teachers (CyberMiSTS) became a foundation for the professional development model for teachers learning new technical-related subjects (NewTechEPD). Utilizing a combination of quantitative and qualitative research approaches, I examined fourteen instances involving educators who participated in the CyberMiSTS workshop, both in-person and through online platforms. This model will enable more teachers to meet the growing demand for STEM-related education in the school system. Based on the findings, an effective professional development program for teachers learning new technical subjects requires the next elements: Materials (such as Learning content and Resources), Activities (including Hands-on activities, Targeted research, and Storytelling), Organizational components (such as Small groups, Format, and Collaboration), and Feedback (including Active ongoing feedback and Peer-review). While this model was evaluated on the teachers learning Cybersecurity, it can also be used in the future for teachers learning other rapidly growing subjects that can be brought to the K-12 level in the near future. This model can also become a baseline for other models or can be modified to be used in other areas of application. [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.]