Proposes a theoretical model of cognitive development and applies this model to the secondary analysis of two large-scale studies which focus on the acquisition of formal operational schemata by adolescents in the United States and Israel. Results support the "unity" hypothesis of cognitive development that the various schemata of formal…

Gifted and highly gifted girls in grades four to six were given Piagetian-type manipulative problem-solving tasks reflecting formal operations. Although Flavell suggested that a chronological age of 10 years was necessary for successful completion of these tasks, time allowed was a more valid predictor. (LMO)

A task was developed to differentiate the reasoning of elementary school students in fifth, sixth, and seventh grades. Subjects completed 16 matrices containing two, three, or four dimensions and varying in the embeddedness of the dimensions. They also solved a formal operational task assessing ability to isolate, exclude, and include variables.…

Investigated the relationship between the development of formal operations and the formation of ego identity in adolescence. Obtained significant positive correlations between combinatorial ability and degree of identity, suggesting that high identity may facilitate the application of combinatorial operations. Found some gender differences in task…

In an attempt to accelerate the development of formal operations in average young adolescents, up to 30 intervention lessons relating to all formal schemata were given by science teachers, over a period of 2 years, to classes in eight British schools. Boys starting the program aged 12 years-plus showed a pre-test, post-test effect size on…

A common concern raised by teachers from secondary schools and junior colleges in Singapore is the apparent inability or reluctance of adolescents to think critically and originally. Adolescent thought processes are probably shaped by the change in intellectual pace and quality between the primary and secondary school curriculum. This study of…