M E. Mavhunga

University of Witwatersrand (SOUTH AFRICA)
It is commonly accepted that Pedagogical Content Knowledge (PCK) has a topic-specific nature. However, the challenge remains that generic PCK models are largely used in teacher education programmes. In our previous study we presented a theoretical framework that distinguishes a topic specific PCK (TSPCK) from a generic PCK construct, and showed that its implementation as an intervention in a chemistry teacher education programme resulted in a statistically significant improvement of PCK in the specific topic (Mavhungaa, 2013). In this paper, we report on an investigation that explored the transferability of learnt reasoning in developing TSPCK in one chemistry topic (‘the particulate nature of matter’) to the development of TSPCK in a novel topic – Chemical Equilibrium. We ask the question: To what extent is learnt pedagogical reasoning as based on the use of knowledge components of TSPCK transferable across a chemistry topic? The pedagogical reasoning and action framework, developed by Shulman (1987) provides a process of reasoning about teaching. Key to Shulman’s framework is the element of transformation of content knowledge. We have expanded on the idea of reasoning by identifying five knowledge components which when used to reason through concepts of a topic, transformation of content emerges.

These five knowledge components are:
(i) Sudents’ Prior Knowledge,
(ii) Curricular Saliency,
(iii) What is difficult to understand,
(iv) Representations and
(v) Conceptual teaching strategies.

We employed a mixed method (MM) research design with 38 chemistry pre-service teachers in a teaching methodology class in their third (3) year of study towards a teacher qualification - B Ed degree in South Africa. An intervention based on explicit discussion of components of TSPCK was conducted over a period of 6 weeks comprised of 3 hour sessions a week. The topic of ‘particulate nature of matter' was used as the topic whose concepts are reasoned out to generate knowledge for teaching. The data collected constituted students submitted examination equivalent task scripts. The task required pre-service teachers to use the learnt pedagogical transformation process to engage with a novel topic – Chemical Equilibrium generally perceived to be difficult and abstract. The examination equivalent task was structured as a vignette prompting natural open ended responses on the five TSPCK knowledge components. In summing up the individual scores, pre-service teachers scored on aggregate a score of 3. According to the TSPCK rubric used, a score of 3 corresponds to a 'developing TSPCK'. The measurements generated fit statistics on the Rasch statistical model within the range of -2 and +2, indicating measurement of a single construct and validity. The reliability was also found acceptable with person and item reliability indices of 0.79 and 0.96 respectively. The ‘developing' category is one level less to be exemplary thus the findings are encouraging signalling evidence of transfer of reasoning and the development of TSPCK in the novel topic of Chemical Equilibrium.

[1] Shulman, L. S. (1987). Knowledge and teaching: foundations of the new reform. Harvard Educational Review, 57(1), 1-22.
[2] Mavhungaa, E., Rollnicka, E. (2013). Improving PCK of chemical equilibrium in pre-service teachers. African Journal of Research in Mathematics, Science and Technology Education, 17(1-2), 113-125.