A thesis submitted to the Faculty of Education in fulfillment of the requirements for the Degree of Doctor of Education (Science Education) in the Department of Mathematics, Science and Technology Education at the University Of Zululand, South Africa, 2012. / This study sought to determine the conceptual difficulties experienced by grade 12 physical science learners with regard to mechanics. It also sought to identify the most prevalent alternative conceptions among grade 12 physical science learners in the area of mechanics, and develop interventions to alleviate the identified conceptual difficulties and alternative conceptions. In this regard, the study compared the effectiveness of a traditional lecture, outcomes-based education (OBE) and blended instructional approaches in alleviating or overcoming the identified conceptual difficulties and alternative conceptions concerning mechanics. The aspects of Mechanics dealt with in this study were: work and energy, motion on the inclined surfaces, projectile motion, force concept, static objects and Newton’s Third Law of Motion. In addressing the above research problem, the study developed and presented a theoretical and conceptual framework derived from the review of relevant literature, in line with the research questions of the study. The conceptual framework developed was based on the constructivist views of learning. A total of one hundred and forty (140) grade 12 physical science learners from Empangeni Education District were involved in this study. The study followed the quasi-experimental non-equivalent comparison-group research design. Though quantitative in design, the study also used qualitative research methods. Thus, both quantitative and qualitative data were collected. From the quantitative data, the findings showed highly statistically significant gains between pre- and post-test scores of OBE and blended approaches in particular. The average normalised gain score concept was also used determine the most effective instructional approach. Convenience sampling was used to select participating schools. A Test in Basic Mechanics (TBM) was designed to assess the learners’ understanding of the most basic concepts in mechanics. The TBM was administered both as a pre- and post-test to the three groups (traditional, OBE and blended groups) to determine the level of experience, knowledge, pre-existing alternative conceptions, level of understanding of basic concepts and principles on mechanics topics identified at the start of the investigation. As a pre-test, the TBM was also used to identify the specific conceptual difficulties and alternative conceptions in mechanics. The identification of the conceptual difficulties and alternative conceptions after the pre-test was followed by three instructional interventions (the traditional, OBE and the blended approach). The three interventions addressed the same mechanics topics mentioned above. These interventions were then followed by post-tests to ascertain the effectiveness of the interventions in addressing the identified conceptual difficulties and alternative conceptions, as well as any conceptual difficulties and alternative conceptions which were resistant to change even after the interventions. The results revealed that the learners experienced conceptual difficulties with regard to (a) resolving the components of the weight; (b) work concept; (c) work-energy theorem application; (d) kinetic energy concept; and (e) principle of conservation of mechanical energy application. Regarding the most prevalent alternative conceptions in mechanics, learners held eight alternative conceptions related to kinematical and dynamical concepts. Alternative conceptions held by the learners in mechanics concerned the following: (a) the acceleration and velocity of projectile motion; (b) weight/mass of an object as related to Newton’s Third Law of motion; (c) force concept; (d) objects in motion; (e) static objects; (f) Newton’s Third Law of motion; (g) acceleration of projectiles; and (h) active force. The average normalised gains for the traditional, OBE and blended instructional approaches were (g) = 0,20; (g) = 0,30; and (g) = 0,60, respectively. This confirmed the statistical analysis computed using One Way Analysis of Variance (ANOVA), that the blended instructional approach was the most effective instructional approach in alleviating the conceptual difficulties and alternative conceptions in mechanics. Qualitative data showed that most of the pre-existing conceptual difficulties and alternative conceptions appeared to have been alleviated, although not completely overcome by the interventions. There were statistically significant differences that were found among the traditional, OBE and blended instructional interventions. It is therefore noted that the blended instructional approach to teaching and learning can have a significant contribution to overcoming conceptual difficulties and alternative conceptions in mechanics, and the improvement of efficiency of learning. The study concluded that conceptual difficulties and alternative conceptions in mechanics could best be alleviated using the blended approach to teaching and learning. A number of recommendations were also made. Some alternative conceptions were resistant to change in the face of the traditional lecture based teaching. This meant that a more powerful teaching technique had to be devised. Thus, physical science educators should be encouraged to use the blended approach to teaching and learning in order to accommodate all learners in a class. Blended teaching and learning is mixing of different teaching and learning environments – mainly manifested in combining face-to-face instruction with the computer mediated-instruction. In one class of learners there are different learner characteristics. Learners learn in different ways like learning through lecture (telling), discussion, problem solving, practical work, discovering, experimenting, using pictures and diagrams, videos and demonstrations.

Thesis (Ed.M.)--Boston University

Magister Educationis - MEd (Mathematics and Science Education) / The purpose of this paper is to investigate whether the teaching of electric circuits in Grade 10 Physical Sciences using a conceptual change approach would enhance learners' understanding of the concept. The conceptual change approach is a process whereby concepts and relationships between concepts change over the course of an individual's lifetime. The process whereby conceptual change occurs is of central interest in helping to understand the process of learning, and is also important when considering the design of instruction. The study was conducted at a secondary school in a small town in the Karoo. Purposive sampling was used to select the sample of a Physical Science Grade 10 class. A mixed method approach was used to observe the effectiveness of the conceptual change approach - four conditions must exist before a conceptual change is likely to occur: (1) assess learners' dissatisfaction with their existing concepts; (2) the new concept must become intelligible; (3) the new concept must appear plausible; and (4) the new concept must be fruitful. All learners' total scores for the pre-test and post-test were calculated and recorded and total scores were statistically analyzed. This study could provide means to improve science teaching and learning. The learners were assisted to discover what was not clear to them, they were encouraged towards deeper understanding and to use their own knowledge to make sense of new concepts. The conceptual change approach could be used effectively by the teachers as it will assist to remove misconceptions learners have prior to the learning of new science concepts.