Constructive use of authoritative sources in science meaning making

The role of authoritative sources of information in a constructivist learning environment has always been ambiguous, especially in science learning where there is a bountiful of knowledge readily available in various sources. Taking a social semiotics perspective in this study, we take the view that authoritative sources are inscriptions of cultural artifacts and science learning involves meaning making of these cultural artifacts. In studying the meaning making process of a group of students doing Problem-based Learning, our findings show that authoritative sources played an important role in deepening and expanding students’ scientific knowledge. We also found that constructive use of authoritative sources involves interpretation of meaning in context. Therefore, we conclude that this structural coupling of authoritative sources and context for meaningful sense making has to be taken into consideration in the design of learning environment. The use of authoritative sources of knowledge, like textbooks, experts and teachers, is often associated with transmission mode of instruction (Scardamalia & Bereiter, 1999). The “knowledge” encoded in books or dispensed by experts are often considered as the ultimate truth to be transmitted to the learners, with due diligence given to the fidelity of transmission so that learners will acquire the valid content rather than develop misconceptions. For this reason, the use of authoritative sources is thought to run contrary to meaning making in a constructivist learning environment, in which students take on an active role in building knowledge through collaborative efforts. The consequence could be a total abstinence from authoritative sources in such a learning environment. This action may, however, deprive the learners of potential resources that could facilitate their construction of understanding. In an attempt to overcome the ambiguous role of authoritative sources in constructivist classrooms, Scardamalia (2002) proposed “constructive use of authoritative sources” as one of the 12 principles for Knowledge Building (p. 77). This principle defines the use of such sources for informing and producing iterative cycles of idea improvement (Zhang, Scardamalia, Lamon, Messina & Reeve, 2007). In other words, it suggests a meaningful deployment of authoritative sources for continual meaning making. In the context of science learning where there is bountiful of scientific information recorded over the course of history and made readily available in various forms of media, what does it mean to use the authoritative sources constructively? In this study, our goal is to find out the process in which authoritative sources are used constructively in mediating science meaning making. Using a social semiotics perspective of science learning, the study seeks to answer the research question “how do authoritative sources mediate effective science meaning making?” using a social semiotics perspective of science learning. Social Semiotics Perspective of Science and Science Learning From a social semiotics perspective, science is a particular way in which people within a science community make sense of the world with different signs and symbols (Lemke, 1990). From this perspective, science is not so much a set of truth to be discovered. Rather, scientific knowledge is a human construction of a system of meanings (for example, concepts, theories and principles) with various forms of semiotic resources such as language, mathematics, diagrams and techniques. This system of meanings is what we come to know as scientific knowledge (Halliday, 1993). The construction of scientific knowledge is a meaning making practice that involves the abstraction of worldly phenomena and representation of physical actions, objects and events with signs or symbols. These semiotic resources function as representation of the physical world and form the social tools with which community members could draw upon for meaning making. Members of the science community draw from the system of semiotic resources to construct scientific knowledge. When used repeatedly and regularly, they become recognizable within the community and become the institutionalized ways of talking and writing among the community members. These stable semiotic structures become the scientific knowledge that is deployed within the science community. For example, the Newton’s Second Law of Motion states that the acceleration of an object is dependent upon two variables: the net force acting on the object and the mass of the object. Mathematically, it is usually represented by F=ma. The terms Force, Mass, and Acceleration are abstract representations of physical phenomena that our senses can detect. These scientific concepts are further used to construct scientific laws that depict their relationships which can be represented in mathematical symbols. Thus, the abstraction of physical phenomena with scientific concepts allows us to build a system of scientific meanings. Therefore, a newcomer into the science community has to appropriate the unique system of social semiotic tools for making meaning of, for and with them in order to participate meaningfully in the meaning making practices of the community. Embodiment of Scientific Meaning in Authoritative Sources Authoritative sources are credible information repository of scientific knowledge constructed by members of a scientific community over a period of time. They can come in various media (such as books or phonic airwaves) in which scientific meanings are represented with the social semiotic resources, particularly linguistic resources, of the scientific community. Examples of authoritative sources include books, Internet resources, experts and teachers. In these authoritative sources, products of meaning making practices in the scientific community are made permanent through the inscription of signs and symbols (Stahl, 2006). However, these inscriptions carry no meaning in itself although the scientific community has imbued meaning onto them. Therefore, repeating the particular words verbally or writing them in verbatim does not constitute meaning making. Instead, it is the ability to deploy these systems of meaning strategically so that community members perceive the actions as meaningful that constitute the constructive use of authoritative sources. More specifically, a newcomer into the scientific community is not making any meaning of these symbolic inscriptions found in authoritative sources until they are brought back to life by human interpretation. Thus, students need to learn to interpret meaning embodied in these artifacts. They have to deconstruct the meaning inscribed in these artifacts and reconstruct its meaning in a particular context. It is in this respect that we refer to as constructive use of authoritative sources for science meaning making. In the following sections, we describe a study which looks at how authoritative sources can be used constructively for science meaning making. We report five instances of this meaningful use of authoritative sources by a group of five students in a Problem-based Learning (PBL) classroom as they went about solving a science problem.