In this study, the authors investigate the ways in which young students demonstrate their critical mathematical thinking (CMT). Students aged 5-6 who are beginning their first formal year of education participated in the study. Data is presented from individual clinical interviews undertaken with 16 students. These interviews were analysed using…

The structure of Russians' life course has never been studied in depth; the only exception is demographic studies regarding marital status and age at childbirth. Principles that define life trajectories should also be examined. The "adult" concept is one of a number of important concepts in the general structure of life planning. This…

Intraindividual variability is a key component in explaining children's development and learning. Studying this type of variability on the micro-timescale can help us understand real-time constructive processes and the subsequent long-term development. The aim of this article is to study the process of children's understanding of…

A schema is best understood as a statistically defined concept. Schematic concept formation consists of abstracting the common elements or properties of a defined class in a schema. Thereafter, both discrimination and retention are facilitated, since only deviations from the schema need be processed for any particular class exemplar. In the…

This paper describes three classification criterion tasks and the rationale for their selection. A set of parameters is defined and then used to describe the item format for the test. The test format and content domain are presented and discussed. Sample testing directions and materials are appended. (Author)

Examines the role of basic cognitive-processing efficiency as the source of developmental variance in cognitive performance. Two experimental tasks, memory and visual scanning, were used to investigate age effects on the search-processing parameter. Subjects were 9-, 11-, 13-, and 15-year-old children. (CM)

Three longitudinal studies examined means-ends behavior of 6- to 8-month olds. Found that intentional means-end behavior increased between 6 and 7 months, with 7-month olds' performance influenced by the presence of a toy on the cloth. Performance was the same when cloth was attached to or separate from the toy. By 8 months, infants adjusted…

A total of 270 children from 3 ethnic groups were tested for understanding of concepts of heating and cooling. A strong horizontal decalage effect was seen, with children of all ethnic groups using more sophisticated explanations at earlier ages for heating than cooling. Implications for developmental theory are discussed. (SLD)

This study examined the transition from concrete to formal operations in very bright children in an effort to determine whether high ability in concrete operations would carry over into formal operational ability, and also to investigate precocity in regard to formal operations. Subjects were 38 white middle-class children ranging in age from…

The rule assessment approach was used to examine five-, eight-, eleven-, and twenty-year-olds' concepts of time, speed, and distance. (CM)

Fifty children, ranging in age from 4 to 10, were individually administered a series of tasks involving different combinations of 2 items selected from a discrete set of items. Analyses of their performances revealed a series of six, increasingly sophisticated, solution strategies ranging from random number selection of items to a systematic…

The conceptual views of homeostasis held by students (n=300) in seventh grade life science, tenth grade biology, and college zoology were examined. A biographical questionnaire, the results from two Piagetian-like developmental tasks, and a concept evaluation statement of homeostasis were collected from each student. Understanding of the concept…

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)

A group of 105 lower-lower middle class kindergarten children were tested on a set of single variable classification tasks and related-component tasks dealing with color and number. Children who failed to reach criterion on the classification test were randomly assigned to one of five experimental groups, stratified on the basis of performance on…

The role of language in conservation tasks and the development of the concept of conservation of quantity in young children are investigated in this study. A total of 50 children, aged 3.0 to 4.7 years, were divided into three groups according to age with a large number clustered around age 4.0 years. Children were randomly assigned to one of two…