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…

This study investigated the development of length measurement ideas in students from prekindergarten through 2nd grade. The main purpose was to evaluate and elaborate the developmental progression, or levels of thinking, of a hypothesized learning trajectory for length measurement to ensure that the sequence of levels of thinking is consistent…

Using nationally representative data from the Longitudinal Study of Australian Children (LSAC; N = 5,107), this study assessed prospective connections between children's early education and care (EEC) experiences from infancy through preschool and their cognitive and behavioral functioning in 1st grade. Incorporating 6 waves of data, analyses…

The purpose of this study was to develop a new Greek phonological awareness test for preschool and primary school age children (ages 5-7) in Greece and Cyprus. A new phonological awareness test with 168 items was individually administered to 132 students (60 students in Cyprus and 72 students in Greece) from five urban, five semi-rural, and three…