A total of 61 children from first through sixth grades participated in four balance-scale and four inclined-plane problem types in a study testing for invariance of subject classifications as rule-users across problems whose products differed but whose type did not. Results indicated that many children's classifications differed across…

Two studies with 3-, 4-, and 5-year-olds examined whether young children can differentiate expertise in the minds of others. Findings indicated that all children could correctly attribute observable knowledge to familiar experts, such as a car mechanic. Preschoolers had difficulty making attribution of knowledge of scientific principles to…

Six match-to-sample picture/object selection experiments explored 3- to 5-year-olds' knowledge about superordinate words and acquisition of this knowledge. Findings indicated that number of standards (one versus two), types of standards (different versus same basic-level categories), and nature of representation (pictures versus objects)…

Results indicates that awareness of the facilitative effect of categorization on recall increases with age, particularly during the early grade-school years. (Author)

Two studies examined whether infants' category discrimination in an object-examination task was based solely on an ad hoc analysis of perceptual similarities among the experimental stimuli. Findings indicated that 10- to 11-month- olds' responses varied systematically only with the presence of a category change, but not with the degree of…

In one experiment, second and fourth graders used more categorical information when they made inferences than did preschoolers. In two other experiments, second graders, but not preschoolers, distinguished between categorical information and appearance when they made inferences about known concepts and familiar properties. (BC)