This study took place at a private high school in the Kavango region with my 32 grade 10B learners as the research participants. Its objective was to investigate how the grade 10 learners make sense of concepts on refraction of light through exploring their cultural beliefs/everyday experiences about the rainbow. This research study was essentially triggered by my own classroom experience of teaching the topic on refraction of light. In order to achieve the goal of this research, a qualitative case study located within an interpretive paradigm was adopted. To gather data I used multiple data gathering techniques such as brainstorming session, learners conducting interviews in the community, practical activities and focus group interviews. This resulted in descriptive data that qualified to be analyzed in a qualitative way. The themes that emerged from the generated data were coded using upper letter cases and various colours. A methodological triangulation was employed by using multiple data generation techniques. Member checking during focus group interviews also ensured validity in this case study. The findings of this study revealed that the use of learners’ cultural beliefs/everyday experiences can be used to enhance learner engagement, meaning making and conceptual development during the science lessons. In addition, the ways in which practical activities are designed and presented to learners in the science classroom determine learners’ participation and conceptual attainment. Therefore, based on my research findings, I recommend that teachers need to be trained to be able to elicit and integrate learners’ cultural beliefs/everyday experiences in conjunction with hands-on practical activities which focus on conceptual development during their science lessons. However, although this study had many benefits, it also showed that it is not easy to close the gap between learners’ prior everyday knowledge and school science. This warrants further research.

The purpose of this study was to examine whether teaching materials designed around fourth graders' preconceptions effectively produced conceptual change about light propagation. Four Taiwanese fourth-grade intact classes (194 subjects), taught by two teachers, participated in this study. The experimental group was exposed to the conceptual change materials (CCM), and the control group was exposed to the current traditional materials (non-CCM). A 10-item paper-and-pencil instrument for assessing conceptual change was developed, which included three categories: Category I, a window image, a phenomenon children observe in life experiences; Category II, a pinhole image, a classroom demonstration of how light travels; and Category III, shadows, an advanced application of light propagation. T tests were employed to assess differences between the pretest and posttest in each group. ANCOVA with the General Linear Model procedure was used to assess differences between the control and experimental groups. No teacher effect and no interaction between pretest and treatment were found in the procedure; therefore, pretest scores were used as the covariate and posttest scores were used as the response in the analysis. Results revealed that, both in the overall test and in Category I, significant differences existed between the experimental group and the control group after the teaching interventions. However, no significant differences existed between the groups in either Category II or Category III after teaching interventions. Children in the experimental group performed significantly better than did children in the control group in Category I (t=-2.44, p<.05 posttest; t=-2.57, p<.05 delayed posttest), but there was no significant difference between the groups in Categories II and III. CCM appears to work better in life application than in classroom activities and advanced application. The study suggested that the CCM teaching approach was effective, but the low percentage (55%) of the scientifically accepted concepts retained after teaching intervention needs to be improved. The test-retest stability between posttest and delayed posttest indicated that the CCM teaching approach had a lasting effect after two weeks. / Graduation date: 1996

A research report submitted in partial fulfillment of the requirements for the degree of Master of Science in Education at the Faculty of Science, University of the Witwatersrand, Johannesburg. / The aim of this study was to determine whether alternative conceptions about interference and diffraction do indeed exist, to identify the most important of these conceptions and to determine whether these conceptions relate to textbooks, as one of the main sources of students' knowledge. An analysis of secondary level textbooks and tertiary level non-calculus textbooks revealed that presentations of constructive and destructive interference, diffraction and other related aspects are treated inconsistently and in some cases contradictorily by different authors. The research instrument was a Physical Optics test which Physics students of the Technikon Pretoria wrote. This test revealed that alternative conceptions on elementary principles of interference and diffraction of light do exist and that they relate to textbook presentations. This study reveals that (i) the terms in phese and out of phase are not consistently used in different textbooks; (ii) the definitions of constructive and destructive interference in terms of phases cause major aiternative conceptions, (iii) the interrelation between interference and diffraction is not clarified. / AC2017