By varying task requirements within a common procedural framework, four experiments established conditions under which children exhibit different understandings of life. Overall, results suggested that even four- and five-year-olds know that people and other animals are alive and that almost all "inanimate objects" are not. (Author/RH)

Employed a trial-by-trial analysis of spelling-strategy use to examine whether the overlapping-waves model could account for strategy choices in spelling for children tested in first and second grade. Found that the model was useful for understanding the development of spelling, despite the fact that explicit use of backup strategies had a minimal…

Two experiments examined development of economic understanding among 5-, 7- and 9-year-olds. Found that most 5-year-olds understood the goal of acquiring desired goods, and most 7- and 9-year-olds also understood the goals of seeking profits, acquiring goods inexpensively, and competing successfully with other sellers. Results suggest that older…

This study tested three hypothesized mechanisms through which explanations might facilitate problem-solving strategy generalization in kindergarteners through second graders. Results suggested that explanations facilitated generalization through the creation of novel goal structures that enabled children to persist in use of the new strategy…

Two experiments examined kindergartners', first graders', and second graders' numerical estimation, the internal representations that gave rise to the estimates, and the general hypothesis that developmental sequences within a domain tend to repeat themselves in new contexts. Development of estimation in this age range on 0-to-100 number lines…

Three experiments involving balance scale problems were used to characterize and explain developmental differences in three domains of children's thinking: existing knowledge about the problems, ability to acquire new information about them, and process-level differences underlying developmental changes in the first two areas. (BW)

Investigated the serial recall strategies of 96 children aged 5-8 years by applying a theoretical and methodological approach originally developed to investigate preschoolers' arithmetic strategies. Results indicated the use of multiple approaches for serial recall and adaptive strategy choices. (RJC)

Describes three experiments that examined how children (4- to 11-year-olds) use their knowledge of the attributes of living things to infer whether particular objects are alive. (HOD)

This study examined 6- to 8-year-old Slovenian children's acquisition of matrix completion proficiency and compared microgenetic and age-related changes on the task. Microgenetic analyses indicated that: variability of children's errors increased before they discovered the correct strategy, the correct strategy became dominant shortly after…

This paper describes and discusses three studies concerned with the representation of children's knowledge as revealed in the ways that children, ages 5 to 17, perform a scientific induction task. A variant of Piaget's balance scale prediction problem was chosen as the experimental task; a formal model for different levels of children's knowledge…

This paper presents a framework for conceptualizing the different ways in which instructions in experimental tasks may be misunderstood. Five possible types of misunderstandings are identified and discussed: (1) misunderstanding of a particular term in the instructions; (2) misinterpretation of a task because the instructions are difficult to…

Analyzed 1.5- and 2.5-year-olds' problem solving and learning. Found that changes in toddlers' strategies could be assessed reliably on a trial-by-trial basis, that changes followed the basic form predicted by the overlapping waves model, and that analyses could reveal information about the qualitative and quantitative aspects of their learning.…

This paper reports two experimental studies of the development of time, speed and distance concepts in children. In Experiment I subjects (12 in each of four age groups: 5-, 8-, 11-year-olds, and adults) were asked to judge which of two electric trains on parallel tracks went faster, for the longer distance, or for more time. Subject's knowledge…

Describes and discusses the rule-assessment approach, a new research strategy for studying developmental sequences in children's acquisition of knowledge. Four experiments were conducted to illustrate the utility of this approach across a variety of concepts and a wide range of ages (three-year-olds to college students). (Author/CM)