Classroom placement of twins is an ongoing issue for educational policy. Many educational jurisdictions have standard policy most commonly founded in the belief that separation supports individual identity, personal development and academic opportunity. This study examined the effects of classroom placement in a sample of 560 twin pairs whose…

The effects of selective missingness on the size of observed correlations between scores derived from peer assessment procedures were examined with a sample of 719 boys and girls drawn from 57 peer groups in seven schools in Montréal, Québec, Canada or Barranquilla, a city on the northern Caribbean coast of Colombia in Latin America. Peer groups…

Data from 790 older school-age (M[subscript age] = 10.2 years, SD = 1.2 years) girls (N = 427) and boys from Barranquilla, Colombia (N = 449) and Montréal, Canada (N = 331) were used to replicate findings reported by Valdivia et al. (2005). This prior study revealed contextual variations in the association between two measures of social behavior,…

The present study examined, within a longitudinal family-informed design and across middle childhood, the predictive associations between preference for solitude and social wariness, two forms of social withdrawal, and peer difficulties. Specifically, preference for solitude, rather than social wariness, was expected to predict peer victimization…

Multivariate analyses were conducted to clarify the nature of the influences of parental values on social behaviours of kindergarteners in the context of socio-demographic variables and sex of participants. This study included 217 mothers and 172 fathers from the same families, who completed a socio-demographic questionnaire and a new Q-sort that…

An exception to most observational studies examining sex differences is Ladd's (1983) study of popular, average, and rejected children, which reported sex differences within as well as across groups. Like Ladd's research, the present study looks at sex differences within and across subsamples of boys and girls, comparing the playground behavior of…

Three studies focused on prediction of teen motherhood, complications during childbirth, multiparity, and close spacing of births; dropping out of school and teen parenthood; and prediction of child behavior from mothers' childhood characteristics. Found that mothers' childhood aggression predicted negative outcomes in each area of risk,…