Explored whether a system between written place-value system and base-10 manipulatives helped children understand place-value. Found evidence that the intermediate system helped children differentiate between face values and complete values of digits in multidigit place-value number representations, and to grasp that the sum of the digits'…

Compared kindergartners', third graders', and undergraduates' understanding and attribution of randomness. Found that kindergartners' interpretations were deterministic or outside the determinancy-indeterminancy frame. Most third graders had some grasp of randomness; their interpretations were less dominated by false attribution of determinism…

This interview study gathered information about the prior knowledge and thinking of kindergarten to third- graders regarding the supply of water, heat, and light to modern homes. Findings indicated that students possessed only limited and spotty knowledge about utilities in modern homes. Within general trends, there was evidence of growth in…

Examined discourse components, interaction patterns, and reasoning complexity of eighth-graders in two science classrooms as they constructed mental models of the nature of matter. Found that teacher-guided discussions were more efficient for attaining higher reasoning levels and higher quality explanations, but peer discussions were more…