Background: Children with language impairment (LI) show heterogeneity in development. We tracked children from pre-school to middle childhood to characterize three developmental trajectories: resolving, persisting and emerging LI. Methods: We analyzed data from children identified as having preschool LI, or being at family risk of dyslexia,…

The relations among various spatial and mathematics skills were assessed in a cross-sectional study of 854 children from kindergarten, third, and sixth grades (i.e., 5 to 13 years of age). Children completed a battery of spatial mathematics tests and their scores were submitted to exploratory factor analyses both within and across domains. In the…

This study compared the validity of chronological age, a standardized algebra prognosis test, standardized verbal and quantitative scales derived from an achievement test battery, and an objective measure of formal or concrete stages of Piagetian cognitive development for predicting final examination scores and course grades in high school…

The Number Test of the ACER Mathematics Profile Series, contains 30 items, for each of three suggested grade levels: 7-8, 8-9, and 9-10. Raw scores on all tests in the ACER Mathematics Profile Series (Number, Operations, Space and Measurement) are converted to a common scale called MAPS, a major feature of the Series. Based on the Rasch Model,…