The purpose of this research was to identify the barriers that upper-secondary school science and mathematics teachers face during the teaching process in economically disadvantaged regions (Hakkari, Turkey and Swansea, UK). The research design was comparative case research and pursues qualitative methodological approach in collecting and analyzing the data about the barriers that teachers are encountering during the teaching process. The research sample consisted of 24 science and mathematics teachers from different upper-secondary schools in Hakkari and Swansea. Semi-structured interview forms, were developed and employed to collect the data. The thematic analysis was used to analyze the obtained data. The results revealed different categories in understanding the situations that science and mathematics teachers confront in both cases; student-related issues, pedagogical issues, teachers’ lack of subject knowledge and socio-economic and cultural-based issues. As student-based barriers, lack of prior knowledge, students`attention span, and interest; and regarding teachers-based barriers, teachers` lack of class management and communication skills, and lack of student-centered methods found as similar barriers. Language and socio-economical problems were also shared barriers for both cities. In addition to those barriers, political and family-based issues which hindered educational attainment found as the main barriers by science and mathematics teachers in Hakkari.
Keywords: comparative case research, mathematics teachers, science teachers, teaching barriers.