A combination of theoretical perspectives is used to create a rich description of student reasoning when facing a highly-geometric electricity and magnetism problem in an upper-division active-engagement physics classroom at Oregon State University. Geometric reasoning as students encounter problem situations ranging from familiar to novel is described using van Zee and Manogue's (2010) ethnography of communication. Bing's (2008) epistemic framing model is used to illuminate how students are framing what they are doing and whether or not they see the problem as geometric. Kuo, Hull, Gupta, and Elby's (2010) blending model and Krutetskii's (1976) model of harmonic reasoning are used to illuminate ways students show problem-solving expertise. Sayer and Wittmann's (2008) model is used to show how resource plasticity impacts students' geometric reasoning and the degree to which students accept incorrect results. / Graduation date: 2013

Problem-based learning (PBL) is an active teaching strategy that could be implemented in the South African educational system to assist in developing problem-solving skills, critical thinking skills, collaborative skills, self-directed learning and intrinsic motivation in students. Even though it is not easy to drift from a teacher-centred strategy to a student-centred strategy, but this drift is supposed to be a paradigm drift for the nation. ‘Physics is difficult’ has been the anthem of students in South African high schools. This has led to lower pass rates in physics and as a result low physics career person in society. Physics students in high schools need to be exposed to the PBL strategy since the PBL strategy focuses on real-life problems to develop problem-solving skills, critical thinking skills and self-directed learning in students which are the skills needed for concept formation in Physical Science. Basically, the education of Physical Science students focused on the ability to acquire skills to solve real-life problems. This study focuses on exploring the experiences of high school physics teachers at Entsikeni cluster, South African, when implementing problem-based learning (PBL) in their physics classrooms. The study uses the mixed-method approach where three different research instruments were used to collect quantitative and qualitative data sequentially. Questionnaires, RTOP and interview protocol were employed. The findings of the study indicate that teachers project positive attitudes toward the PBL strategy but may probably not continue to use it because it requires more time than that which is allocated in the Curriculum Assessment and Policy Statement (CAPS) Physical Science document and as a result may not be able to finish their ATP on time. Teachers are teaching physics with no specialization in physics, which probably could lead to poor, pass rates in Physical Science. Teachers were inexperienced in teaching physics in the FET and could probably affect students’ academic performance. It is recommended they apply the PBL strategy to correct the negative effect of their inexperience on students’ performance. It is evident that if inexperienced trained teachers apply an instructional strategy based on research, they tend to develop students' performance as compared to applying the traditional instructional strategy. / Science and Technology Education / M. Sc. (Physics Education)