Children sometimes make "scale errors," attempting to interact with tiny object replicas as though they were full size. Here, we demonstrate that instrumental tools provide special insight into the origins of scale errors and, moreover, into the broader nature of children's purpose-guided reasoning and behavior with objects. In Study 1, 1.5- to…

The development of multiplicative classificatory skills in children between 4 and 9 years of age was investigated by means of two forms of the matrix-completion task. (Authors)

Investigated two developmental implications: (1) that foci for color categories become established and stabilized earlier than boundaries, and (2) that focal judgments are always more stable than boundary judgments. Subjects were 20 kindergarteners, 40 third graders and 40 adults. (Author/SDH)

Reviews Gibson's contributions to the domain of perceptual learning, including her classic experiment concerning the perception of scribbles. Discusses Gibson's research on differentiation and the links between perception and learning, the status of her research and ideas, and her experimental approach. (BG)

Reexamined the theoretical question of early childhood egocentrism by replicating Piaget and Inhelder's mountain experiment with variations to insure the age appropriateness of the task for 3- and 4-year-old children. (SDH)

Study deals with a comparative developmental analysis of performances on the same task by four age groups. (MB)

In contrast to earlier notions, a systems view of an organism's development sees genes as only one component in a hierarchy of influences that produces finished traits and differentiation. Developmental canalization proceeds from genes, behavior, and environment as well as from the coaction of these factors. (BC)