ABSTRACT
The emphasis on practices has emerged from the work of the science historians, philosophers, cognitive scientists and sociologists over the past 40 years. Categorization and classification, however, require scientists to engage in the practice of collecting, analyzing and interpreting data. Models are essential for explanations. Whether it is the particle model of solid, liquids and gases, the Bohr model of the atom or a model of animal cell, once in possession of a model it can be used to construct an explanation. The primary purpose of engaging in practice is to develop students’ facility with that practice, how that practice contributes what we know, and how that practice helps to build reliable knowledge. Knowledge of how we know in the science is reliant on a developing a body of procedural knowledge or concepts of evidence.
