Teachers’ mole concept pedagogical content knowledge and learners’ understanding of the topic: a case of selected secondary schools in Kitwe district.

Abstract

The mole concept is one of the fundamental concepts in chemistry and yet numerous studies carried in various countries in the past four decades have shown that teachers and learners face a lot of problems in teaching and learning of the concept respectively. Currently there seems to be no comprehensive model of the mole concept Content Representations (CoRes) framework to address some of the teaching and learning difficulties of the topic. The aim of this study was therefore to develop the CoRes to guide and enhance teachers' mole concept Content Knowledge (CK) and Pedagogical Content Knowledge (PCK) and consequently learners' understanding of the mole concept. The objectives of the study were to: determine teachers’ mole concept CK; determine learners’ conceptual understanding of the topic; assess the teachers’ mole concept Pedagogical Content Knowledge; identify the underlying sources of teaching and learning difficulties of the topic; and consequently develop a model of the mole concept CoRes framework. The participants were 251 Grade 11 pupils and 30 teachers in six selected secondary schools in Kitwe district of Zambia. The data was collected using multiple data collection methods namely; questionnaire, lesson observations, CoRes framework, test and focus group discussions. The embedded quantitative data was analysed using excel into descriptive statistics. The CoRes framework, three models and modified concept map for conceptual understanding of the mole concept were used to catergorise and analyse qualitative data into themes according to the objectives of the study. The study found out that teachers’ mole concept CK was weak for the development of adequate mole concept PCK for learners conceptual understanding of the topic. Learners performance in the test showed that they lacked the conceptual understanding of most of the concepts and ideas under the mole concepts. Their understanding of the concepts mirrored the conceptual limitations faced by their teachers. The International System of Units (SI) definition of the mole concept, lack of knowledge on the origin and evolution of the concept, inadequate understanding of the linking ideas and the multiple association of the microscopic, macroscopic and symbolic knowledge levels within the conceptual network of the mole concepts by teachers, were some of the identified underlying source of teaching difficulties of mole. Based on the above findings and relevant literature, the study developed a mole concept CoRes framework focused on enhancing learners’ understanding of the topic by addressing the identified teachers’ conceptual limitations and pedagogical challenges. In view of the findings, the study made the following recommendations: replacement of the term ‘amount of substance’ by ‘chemical amount’ in the SI definition of the mole concept, Chemistry Education courses in teacher training programmes to include history and evolution of the mole concepts, the mole concept to be taught in Grade 10 after covering the mole concept, teachers to use conceptual strategies to creatively integrate the three knowledge levels within the conceptual network of the mole concepts, and further research in the area of the proposed mole CoRes framework to enhance teachers’ CK and PCK. Key Words: Mole concept, Pedagogical Content Knowledge, Content Knowledge, Content Representations