Professional development in STEM for science teachers: Examining improvements in lesson planning and implements

In recent years, there has been an increasing emphasis on STEM education and the need for effective professional development (PD) programs to increase teachers' competencies in planning and implementing STEM activities. In this study, the aim was to investigate in depth the effect of a comprehensive STEM PD program on science teachers' competencies in STEM lesson plan preparation and classroom implements. The research design was a holistic single case. The study group consisted of 10 science teachers working in public secondary schools. The STEM PD program included an 80-hour training consisting of four stages in a 6-month period. During the PD program, the teachers prepared at least two STEM lesson plans and carried out STEM classroom implements. The data source of the study consisted of the lesson plans prepared by the teachers and the researchers' observations (observation form and field notes) of the teachers' classroom implements. The results show that the STEM PD program, developed within the scope of this research, contributed to the preparation of lesson plans and in-class implements by teachers. It is recommended that teachers engage in both theoretical learning and practical workshops, distributed across multiple sessions, to enable planning, execution, and experience sharing. The process of identifying deficiencies during implementation and receiving feedback from peers and experts is highlighted as a key strength of the program. © 2025 the Author(s), licensee by AIMS Press.