Students' conceptions of models and how models function in science were assessed by administering a clinical interview about models to a group of mixed-ability seventh and honors eleventh grade students. Students' preconceptions about models, themes that appeared regularly during interviews, differences of themes between the two groups, and the…

A model of the character and mechanism for knowledge restructuring is presented and a model of educational practice designed to facilitate this form of restructuring is described. A broadened and integrated view of assessment and instruction called a portfolio culture, central to the educational model, is discussed. (KR)

In the literature, learners' cognitive development is mainly discussed with respect to changes in learners' content-dependent knowledge (conceptual change or growth). Additional dimensions of time and complexity may also be taken into account to describe cognitive processes in at least three dimensions. We discuss these three dimensions of…