External visual representations in science learning: The case of relations among system components

How do external visual representations (e.g., graph, diagram) promote or constrain students' ability to identify system components and their interrelations, to reinforce a systemic view through the application of the STS approach? University students (N = 150) received information cards describing cellphones' communication system and its subsystem components. One group (n = 82) received a display of cards presenting this information in rich and diverse visual representations and a few text cards. Another group (n = 68) received a single representation display, of text only. Using these card sets, students were asked to identify the cellular systems' components and relations, and to construct new interrelations. Findings showed that, mostly, multimedia enabled better identification and construction of relations of higher component diversity, accuracy, description, and novelty, using a larger number of information cards than did the textual display. Generally, findings suggested that components' saliency and distinctiveness in the visual display afforded a better systemic view. However, curriculum designers and teachers should be aware of cases in which rich multimedia constrained performance.