Flexibility in transforming algebraic expressions is recognized as fundamental for a rich procedural knowledge. Here, flexibility in-depth is proposed as the ability to apply one strategy to a wide range of unfamiliar expressions. In this study, design experiments with four groups of students were conducted to support students' flexibility…

This study investigated the ways in which the technological tool, The Geometer's Sketchpad, mediated the understandings that high school Honors Geometry students developed about geometric transformations by focusing on their uses of technological affordances and the ways in which they interpreted technological results in terms of figure and…

Geometric matrix problems were presented to 11- and 14-year-olds and adults to investigate latency to solution as a function of number of elements (1-3) and of transformations (0-2) that had to be considered for correct solution. At all ages latencies increased as the number of elements and number of transformations increased. (Author/DB)

Two studies to determine how students interact with two microworlds that reflect a constructivist view of learning investigated students' goals during interaction, strategies utilized to achieve their goals, changes in goals during interaction, and common patterns of interaction and learning. Concludes that well-designed games enable students to…