The purpose of the study was to investigate the procedural problem-solving approaches students employ when solving computational problems that involve extensive and intensive quantities of change of state. A sample of 240 Form 3 science students randomly selected from five senior high schools in the Cape Coast Metropolis participated in this study. An achievement test on change of state of matter comprising of five items was used for data collection. The results showed, among other things, that students employ the structured procedural approach when solving change of state computational questions that involve extensive quantities instead of the scientific approach. The study also found that no clear procedural approach was employed by major...