This study compared the behaviors of children who had been in a toddler day care program at least 13 months with children who had been there less than 6 months. The children who had been in the program longer were rated significantly higher in ability to get along with peers, problem solving, ability to abstract, and ability to plan. (JMB)

Results showed that only 32 percent of adult female shoppers in a supermarket were able to use a proportional reasoning strategy to determine which of two sizes of a common item (size ratio 2:3) was the better buy. Performance declined when the ratio was more complex. (JMB)

Surface and relational similarity were examined in two experiments involving isomorphic and nonisomorphic analogical transfer, using direct-mapping and cross-mapping conditions. In the first experiment, third and sixth graders exhibited mapping based on relational similarity more frequently than did kindergartners; in the second, most four- to…

Three experiments examined the role of representations in adolescents' deductive reasoning. Findings indicated that, with age, conditional reasoning improved on tasks containing permission conditional relations; reasoning fallacies increased on tasks containing causal conditional relations. Valid conditional inferences were more common on problems…

College students were assigned to either dyadic or individual problem-solving conditions and were given a series of formal operational tasks. Dyadic subjects solved more problems during the interaction phase than did individual subjects. Among dyadic subjects, interactions were associated with problem solving and pre-to-posttest gain scores. (BC)

A developmental study of elementary school children's use of rule v computation in solving spacial perspective-taking problems. (CM)

This study investigated the emergence of combinatorial competence in early adolescence and the effectiveness of a programmed discovery training procedure. Significant increases in combinatorial skill with age were shown; it was found that the expression of this skill was significantly facilitated if problems involved concrete material of low…

A 10-step scale for assessing development of understanding relationships between honesty and kindness was developed and administered to 113 youths. Results indicated that development moved through 3 stages, as youths age 9-12 demonstrated abstract concepts of honesty and kindness; age 13-15 demonstrated simple abstract relations; and age 16-20…