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.…

The role of content in formal operations tasks was explored in research that systematically varied the content of tasks and children's performance by developmental level and socioeconomic status (SES). Subjects were 110 Icelandic 12-year-olds who had entered a longitudinal study when they were 7 years old. Two extreme ability groups of children…

Assessed the relative availability of Piagetian formal reasoning concepts at different ages in adulthood and examined performance patterns on standardized intelligence tests, logical reasoning, immediate memory span, and personality measures. Results indicated that although the elderly students' performances were generally adequate, their scores…

This research hypothesized that preformal-operational children (before age 11) can improve their ability to write persuasive essays at an age earlier than Jean Piaget's developmental stage model would predict. A Vygotskian social interactionist approach, which claims that adult intervention can help children achieve what may have seemed beyond…