Asking questions is an important way of acquiring information and knowledge and plays a significant role in a child's learning processes. In this study, we examine what characterises the questions asked by children to their teachers in two kindergartens (4-6-year-olds) and six primary school classes (2nd-4th grade) when situated in a natural…

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…

Two ways of measuring change are presented and compared: A conventional "change score", defined as the difference between scores before and after an interim period, and a process-oriented approach focusing on detailed analysis of conceptually defined response patterns. The validity of the two approaches was investigated. Vocabulary…

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…

The aim of the present study was to investigate the performance in arithmetic related to achievement levels in reading and mathematics. Basic arithmetical facts and multi-step calculations were examined. The participants were 941 pupils aged 8 (N = 415), 10 (N = 274) and 13 (N = 252) years. The pupils were divided into four groups by standardized…

Objective: The Bergen Child Study is a longitudinal study of child mental health from the city of Bergen, Norway. We present methods and results from the first wave of the study, focusing on prevalence of disorders, associations with risk factors, and the use of services. Method: The target population included all 9,430 children attending grades 2…