To examine whether children's acquisition of perspective-marking language supports development in their ability to reason about mental states, we conducted a longitudinal study testing whether proficiency with complement clauses around age 3 explained variance in false-belief reasoning 6 months later. Forty-five English-speaking 2- and 3-year-olds…

Adolescents become increasingly sensitive to social evaluation. Some previous studies have related this change to pubertal development. The present longitudinal study examined the role of sociocognitive development. We investigated whether or not the transition to recursive thinking, the ability to think about (others') thoughts, would be…

This handbook is a guide and reference document for those researching the child data files of the 1986-1990 National Longitudinal Survey of Youth, sponsored by the Bureau of Labor Statistics. It describes the child data collection procedures, the nature of the child sample, the child data files available, and the specifics of the child assessments…

One of 10 reports in a longitudinal study of Project Head Start submitted by NTS Research Corporation to the Administration for Children, Youth and Families, this document presents the individual testing battery used for the fall 1979 cohort. The first chapter identifies the skill areas to be tested in an analysis of Project Head Start's…

This final report reviews the second phase of a life-span study of boys with fragile X syndrome (FSX), the most common known inherited cause of mental retardation. Males with the syndrome are more severely affected than females and in males, delays are usually evident in all the developmental domains, although cognitive and communication skills…

Overall correlations between personality/motivation and verbal reasoning, divergent thinking, and creative writing in 1,416 children, aged 10-13 were low, suggesting that classroom climate and teaching methods may affect this relationship. (Tests are appended.) (Available in microfiche from: Carfax Publishing Company, Haddon House,…