Investigation of the development in the understanding of inquiry based teaching of science teachers participated in an inquiry based professional development program

According to the education paradigm adopted in our country, with the effect of the reform movements in the world, teachers are implicitly expected to design and apply activities based on the inquiry approach since 2004 in the science curriculum. This expectation is explicit since 2013. However, it is observed that the practices based on this approach are not sufficiently realized. In this thesis, based on the idea that in-service training programs should be organized in order to reflect the innovations made in the education system to the classroom environment, professional support was provided to the committee of science teachers. The "Inquiry-based Professional Development Program (IB-PDP)", which was carried out in cooperation with the "Professional Development Team" including the teachers, researchers, and subject matter experts lasted for approximately one school period. With the IB-PDP, which is based on the Flexible Inquiry-Based Science Teaching (FIBST) Model, it is aimed for teachers to develop an understanding of inquiry. While the teachers were gaining theoretical knowledge about the inquiry approach, they also tried to reflect the knowledge they gained to the classroom environment. This study was designed as a qualitative case study. Interviews with the teachers and students, observations of teachers' practices and documents, and the field notes on IB-PDP meetings formed the qualitative data. All the collected data were subjected to descriptive analysis. According to the results of the research, it was revealed that before the IB-PDP teachers did not have an understanding of inquiry, and teachers' development was at different levels in six dimensions, which are indicators of the development in their understanding of inquiry after IB-PDP. It has been determined that the students of the teachers who have gained an understanding of inquiry also understand the inquiry approach, and the FIBST Model facilitates the practices of the teachers. Although all the teachers believed in the necessity of this approach, some teachers did not prefer to use it for various reasons. The fact that IB-PDP is oriented towards job-embedded and collaborative work contributed to teachers' understanding of inquiry. The research performed in this thesis also complies with the decisions taken for the professional development of teachers in the Vision 2023 Document.