The aim was to investigate the effects of school mobility on achievement in compulsory school in Sweden for children in out-of-home care (OHC) and not in OHC (NOHC). Register data on background variables from four birth cohorts in the cohort-sequential longitudinal project ETF was relied upon, along with student performance on a test of cognitive…

Modern behavior-genetic studies of twins in the United States, Australia, Scandinavia, and the United Kingdom show that genes account for most of the variance in children's reading ability by the end of the 1st year of formal reading instruction. Strong genetic influence continues across the grades, though the relevant genes vary for reading words…

In this paper, we estimate the effect of pupil's relative age within the first grade of primary school on mathematics and reading test scores at age 15. The main objective is to evaluate the long-term causal effect of relative age in the first grades of primary school on pupil's test in 16 different countries. We use the national rule for…

Genetic and environmental relations between vocabulary and reading skills were explored longitudinally from preschool through Grades 2 and 4. At preschool there were strong shared-environment and weak genetic influences on both vocabulary and print knowledge but substantial differences in their source. Separation of etiology for vocabulary and…