Moll (2002) argued that social constructivism being a socio-cultural theory, advocates the mediation o f learning which occurs because o f social interactions with the knowledgeable individual. The social constructivist perspective learning entails sense making by individual learners through social interactions (Driver, Asoko, Leach, Mortimer, & Scott, 1994; McRobbie
& Tobin, 1997). Knowledge construction happens during individuals’ engagement in tasks, academically or socially. This perspective highlights that knowledge is socially constructed within a society (Moll, 2002). Learning is actively processed whereby learners construct knowledge, meaning and skills which leads to developing ‘new ’ knowledge (ibid).
According to McRobbie and Tobin (1997), active involvement during the mediating o f learning contributes to better understanding o f science. In other words, learning involves constructing one's individual knowledge from one's individual experiences. The concept o f mediating learning is attributed mainly to Vygotsky (1978). Vygotsky’s mediation o f learning incorporated in social constructivism is based on a fundamental concept known as the ‘zone o f proximal development’
(ZPD) which is the region between what a learner can do on his own, and what he can do with the help o f a “knowledgeable other” such as a teacher. Furthermore, his theory highlights the importance o f social interactions during the learning process.
F ig u re 2.1: V y g o tsk y m ed ia tio n m od el Source: (Vygotsky, 1978)
In this study data generation and analysis, relied on Vygotsky’s concepts o f mediation. His mediation triad linking subjects (teachers), object (the problem space or object o f learning) and tools (Figure 2.1) served to unpack the mediation process and the associated challenges that teachers face when teaching electromagnetism. Wells (2002) suggested that “agent-acting-with-
mediational-means” (p.46) is the basic unit describing human activity (practice). The point is that whereas other species act directly upon the object o f interest to them, humans on most occasions interpose a mediating artefact (tool) between themselves and the object o f interest, thereby enabling them to act more effectively. Tools can be physical (hummer, car, pen and paper, etcetera) or non-physical such as concepts, frameworks, policies, language and so forth.
Using Vygotsky’s mediation triad, for instance, the sub-question is unpacked: How do Grade 10 Physical Science teachers help learners to make sense o f concepts on electromagnetism through using easily accessible materials?In terms o f the mediation triad, the absence o f practical activities constrains mediation o f electromagnetism concepts.
2.8.2 Pedagogical Content Knowledge
According to Shulman (1987), pedagogical content knowledge (PCK) represents a “blending of content and pedagogy into understand o f how particular topics, issues are organized, represented, and adapted to the diverse interests and abilities o f learners” (p.8). Shulman puts forward a resilient argument that teachers are people who know something not understood by learners, and it is the teachers who help learners unlock the content knowledge which learners do not understand, using well-structured teaching methodologies.
Cochran, King and De Ruiter (1991) broadened that pedagogical content knowledge (PCK) is an integrated understanding that is synthesized from teacher knowledge o f pedagogy, subject matter content, student characteristics, and the environmental context o f learning, They paraphrased the connotation o f PCK as a concept that uses the understanding o f subject matter concepts, learning processes and strategies for teaching the specific content o f discipline in a way that enables learners to construct their knowledge effectively in a given context.
This knowledge referred to by Shulman (1987) and Cochran et a l. (1991) guides teachers in their teaching practice, encompasses teachers’ knowledge and beliefs with respect to various aspects such as pedagogy, learners, subject matter, and the curriculum and it is also derived from past knowledge and ongoing experiences (Williams, 2012). Shulman (1987) sub-divided PCK into
seven components (subject content knowledge, methodological knowledge with reference to subject content deliveries, knowledge o f the curriculum, general pedagogical knowledge referring to classroom principles and strategies, knowledge o f learners, knowledge o f educational contexts referring to school governance and social structure and knowledge o f educational ends pointing to educational values and purposes, and school philosophy) o f which two are listed and deliberated below:
(a) Methodological knowledge regarding subject content deliveries; and
(b) General pedagogical knowledge referring to classroom principles and strategies.
According Van Driel et al. (1998), craft knowledge is diligently associated to PCK as integration of knowledge which embodies teachers’ accrued understanding in relation to their teaching practice. Concurring, W illiams (2012) articulated that PCK is developed through practice.
Teaching knowledge practices (methodology) is the first PCK component for discussion.
For teachers to be effective in their teaching, Shulman (1986) emphasized that they ought to practice worthwhile forms o f representation o f ideas, the most powerful analogies, illustrations, examples, explanations, and demonstrations-in a word, the ways o f representing and formulating the subject that make it comprehensible to others (learners). Van Driel et al. (1998) agreed with Shulman (1986) that teachers must confidently transform subject-matter knowledge, so that it can be used successfully and adaptably in the communication process between teachers and learners during classroom practice.
In order to remain within the perimeters o f this study, only two o f Schulman’s (1987) components are discussed as they help to brighten the study analysis.
W hile Shulman (1987) conceded that content knowledge develops continuously during practice, Ball, Thames and Phelps (2008) cautioned that teachers must know the subject content they teach and the subject content learners are anticipated to understand. Furthermore, through professional practice, Mann (2005) qualified that knowledge is constructed and developed and this leads to teachers developing a sense o f credibility or congruence.