The sequence of development as hypothesized by Piaget has been confirmed for various groups of children by cross-sectional and longitudinal studies. Such consistency has increased interest in constructing scales based on Piaget's theory according to psychometric principles. Three major problems are discussed which present definite obstacles in the…

This article presents evidence of the reliability and validity of a new paper-and-pencil test of proportional reasoning, Paper-and-Pencil Balance Beam Test. A Total of 627 individuals, aged 8-47, participated in the 3 studies discussed. Results support previous research which correlates performance on proportional reasoning problems with…

The purpose of this study was to design a prototype written test of cognitive development based on the model of Piaget. Although the results were not consistent with Piaget's theory, test development was only partially successful. Specifically, validation of the scales was excellent or poor depending on the perspective. Analysis of the item…