Use of a computer simulation to develop mental simulations for understanding relative motion concepts

Think aloud interview protocols from three high school post-physics student s who interacted with a relative motion computer simulation presented in a predict-observe-explain format are analysed. Evidence is presented for: qua litative and quantitative difficulties with apparently simple one-dimension al relative motion problems; students' spontaneous visualization of relativ e motion problems; the visualizations facilitating solution of these proble ms; and students' memory of the on-line simulation used as a framework for visualization of post-test problems solved off-line. Instances of successfu l and unsuccessful mapping of remembered simulation features onto target pr oblems are presented. Evidence from hand motions and other indicators sugge sting that the subjects were using dynamic imagery in mental simulations du ring the treatment and post-test is presented. On the basis of these observ ations, it is hypothesized that for successful students, dissonance between their incorrect predictions and simulations displayed by the computer init iated the construction of new ways of thinking about relative motion, and t hat the memory of certain simulations acted as an analogue 'framework for v isualization' of target problems solved off-line after the intervention. In such cases we find that interaction with a computer simulation on-line can facilitate a student's appropriate mental simulations off-line in related target problems. Implications for design and use of educational computer si mulations are discussed.