Physics students learning about abstract mathematical tools when engaging with “invisible” phenomena

The construction of physics knowledge of necessity entails a range of semiotic resources, (e.g. specialized language, graphs, algebra, diagrams, equipment, gesture, etc.). In this study we documented physics students' use of different resources when working with an "invisible" phenomenon--magnetic field. Using a social semiotic framework, we show how appropriate coordination of resources not only enabled students to learn something about the Earth's magnetic field, but also about the use of an abstract mathematical tool--coordinate systems. Our work leads us to make three suggestions: 1. The potential for learning physics can be maximized by designing tasks that encourage students to use a specific set of resources. 2. Thought should be put into what this particular set of resources should be and how they may be coordinated. 3. Close attention to the different resources that students use can allow physics teachers to gauge the learning occurring in their classrooms