Effects on adjustment of biological maturation and social timing were compared using data from a longitudinal sample of 335 young adolescents, who were followed from the sixth through eighth grades. (Author/LMO)

It should now be recognized that every child has at least five parallel ages: A "chronological" age, in years, months, and days: a "physiological" age, indicative of physical growth and maturity; a "mental" age, significant of intellectual capacity and ability; a "school standing," or "pedagogical"…

Investigation of the roles of pubertal timing and pubertal status on school achievement for 115 boys and 137 girls followed through grades 6, 7, and 8 indicates that late-maturing boys have the lowest school achievement, whereas late-maturing girls have the highest. Followups at grade 12 indicate few long-term effects. (SLD)

This article discusses development during the early adolescent years with a focus on recent research on the biological, cognitive, self-identity, and motivational changes that occur during this time period and the implications of this research for middle school counselors. Peer influences on early adolescents also are discussed, with the issue of…