Multimedia and understanding: Expert and novice responses to different representations of chemical phenomena

Abstract

In two experiments, we examined how professional chemists (i.e., experts) and undergraduate chemistry students (i.e., novices) respond to a variety of chemistry representations (video segments, graphs, animations, and equations). In the first experiment, we provided subjects with a range of representations and asked them to group them together in any way that made sense to them. Both experts and novices created chemically meaningful groupings. Novices formed smaller groupings and more often used same-media representations. Experts used representations in multiple media to form larger groups. The reasons experts gave for their groupings were judged to be conceptual, while those of novices were judged to be based on surface features. In the second experiment, subjects were asked to transform a range of representations into specified alternative representations (e.g., given an equation and asked to draw a graph). Experts were better than novices in providing equivalent representations, particularly verbal descriptions for any given representation. We discuss the role that surface features of representations play in the understanding of chemistry, and we emphasize the importance of developing representational competence in chemistry students. We draw implications for the role that multiple representations-particularly linguistic ones-should play in chemistry curriculum, instruction, and assessment. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 949-968, 1997. The expansion of the universe, tectonic plate drift, evolution of the species, and molecular structure and reactivity are all scientific phenomena that are not available to direct experience. Whether the phenomenon is cosmological, geological, biological, or chemical, our window on the world is really very small. But perhaps more than other sciences, understanding chemistry relies on making sense of the invisible and untouchable. Much of what is chemistry exists at a molecular level and is not accessible to direct perception. Whereas the experiments used in classroom demonstrations are carefully selected to denote chemical processes by changing color, precipitating a solid, or giving off heat, most chemical reactions in the real world occur at rates that are so fast or slow, or their products are so dispersed, colorless, or odorless, as to make them difficult to detect.

Do student perceptions of teaching predict the development of representational competence and biological knowledge?

“…Studies indicate that students' RC is closely related to students' conceptual understanding of the domain (Kozma & Russell, 1997;Stieff, 2011). However, these studies did not seek to empirically distinguish between content knowledge in the domain (CK) and RC.…”

“…First, we examine students' RC and CK on photosynthesis as well as the relationship between these two constructs. Previous research indicated that students' RC is closely related to students' conceptual understanding of the domain, but these studies did not empirically distinguish between CK and RC (Kozma & Russell, 1997;Stieff, 2011). We would like to answer the following research questions: (1) What role does students' CK play in relation to students' RC and vice versa?…”

“…Science is instead a multimodal discourse utilising a variety of representations (e.g., graphs, diagrams, symbols, formulae) and so interpreting, constructing, transforming, and evaluating different scientific representations are crucial skills for students to build and communicate a conceptual understanding of science (Kress, Jewitt, Ogborn, & Tsatsarelis, 2001;Lemke, 2004;Yore & Hand, 2010). These skills have been referred to as representational competence (RC, Kozma, Chin, Russell, & Marx, 2000;Kozma & Russell, 1997, 2005 and contribute to being scientific literate. Scientific literacy thus comprises of the interacting dimensions of fundamental literacy, including the abilities to construct and interpret scientific discourses (inter alia RC), and the derived understanding about the principles and foundations of science (Norris & Phillips, 2003;Yore et al, 2007).…”

“…There is a growing body of studies that explored how RC is influenced by design factors of representations or by the strategies students use to reason with representations (e.g., Canham & Hegarty, 2010;Kozma, 2003;Kozma & Russell, 1997;Stieff, 2011;Stieff, Hegarty, & Deslongchamps, 2011). However, no study we know of has empirically analysed the interactive relationship between RC and content knowledge (CK) and only a few studies have analysed how teaching practices in authentic classroom settings affect RC (e.g., Hubber, Tytler, & Hastam, 2010;Kohl & Finkelstein, 2006;Prain & Waldrip, 2006;Tytler, Prain, & Peterson, 2007).…”

Integración de visualización científica molecular en el salón de clases

“…Ahora, el aprendizaje asistido por la visualización científica molecular está cambiando la manera en que los estudiantes conciben la química. 9 En un proyecto de investigación cooperativa financiado por la Fundación de la Ciencia Nacional de los Estados Unidos, sobre la visualización molecular en la enseñanza de la química, se encontró que de todos los modelos moleculares considerados, incluyendo los modelos físicos, las herramientas de visualización computacional fueron los que marcaron la diferencia en la manera en que los alumnos asimilan el conocimiento. [10][11][12][13][14][15] La visualización científica molecular se ha utilizado como una herramienta valiosa en el aprendizaje de la química en el salón de clases.…”