The current longitudinal study measured 279 kindergartners' (M[subscript age] = 5.76 years; SD = 0.55; 135 females) place value understanding using both approximate and syntactic measures based on previous evidence that early variation in performance on approximate measures was associated with subsequent syntactic place value understanding. In the…

Research Findings: This study examined age-based developmental trajectories of four key number sense (NS) skills within an accelerated longitudinal design. Using data from 408 preschoolers, ages 45 to 68 months, linear and latent basis growth curves were evaluated. Results indicated growth across NS skills was best represented as nonlinear for all…

Computational estimation is seen as an important mathematical competence. Little is known, however, about the mathematical skills that are predictive of early computational estimation development. The current study longitudinally followed a group of about 350 children at four time points: second (K2, 4-year-olds) and third grades of kindergarten…

Research distinguishes three types of arithmetic: exact arithmetic, computational estimation and approximate arithmetic. Little is, however, known about the interrelationship among these three arithmetic skills and the general cognitive and early numeracy skills that underlie these arithmetic skills. The current study investigates this…

Difficulties in mathematics are argued to stem from impairments of a specialized system of numerical magnitude representation. This study investigates whether different measures of numerical magnitude understanding in kindergarten uniquely predict mathematical achievement concurrently and 6 months later, and also examines the relative explanatory…

The relation between mathematical achievement in early childhood and future academic success is well established. However, the effect of instruction on mathematical performance is less well-documented and often reliant upon self-report instruction measures and standardized achievement measures. Therefore, this study seeks to use observational data…

In this study we investigated the development of 245 kindergarteners' mathematics problem solving (MPS) at two time points within 7 months using a cognitive diagnostic test, which measured three cognitive components (mathematical knowledge and skills, semantic understanding, and quantitative reasoning) with eleven cognitive attributes. The effects…

Drawing on Geary's (1995) evolution-based model of cognitive and academic development, this study investigated the relation between biologically primary skills (vocabulary, executive functions, and visual-spatial processing) and subsequent word reading and calculation. It also examined the extent to which these relations were mediated by…

This study examined cognitive precursors of hierarchical mathematical development. Six-year-old children (n = 258) were assessed on number skills, cognitive skills, and arithmetic 1 year prior to school entry. Skills in advanced arithmetic and advanced mathematics were assessed in Grades 3 and 6, respectively. Path analyses were computed and…

Research Findings: In this research we explore the relationship between young children's number knowledge and their measurement of length. First, we examined 4- to 5-year-olds' (kindergartners') understanding of and preference for using standard or nonstandard units to measure length. Second, we investigated whether the following tasks were…

There is an ongoing debate over the psychophysical functions that best fit human data from numerical estimation tasks. To test whether one psychophysical function could account for data across diverse tasks, we examined 40 kindergartners, 38 first graders, 40 second graders and 40 adults' estimates using two fully crossed 2 × 2 designs, crossing…

The study was conducted to look at differences between children who outgrew and did not outgrow an early diagnosis of mathematical learning disorder (MD; n=13), and peers without MD (n=13). Children were tested at 5, 6, 7 and 10 years of age. About 54% of the children with an early diagnosis of MD still experienced mathematical difficulties at the…

Calculation fluency weaknesses are a key characteristic of children with mathematics difficulties. The major aim of this dissertation was to uncover early predictors of calculation fluency weaknesses in second graders. Children's performance on number sense tasks in kindergarten along with general cognitive abilities, early literacy skills, and…

Children's number sense in kindergarten was used to predict their calculation fluency in second grade (N = 198). Using block entry regression, usual predictors of age, reading, memory, and verbal and spatial cognition were entered in the first block and number sense measures were added in the second block. Number sense measures contributed a…

This study examined the extent to which children's cognitive abilities in kindergarten and their mothers' education predict their single-digit and procedural calculation skills and the covariance of these with reading skill in Grade 4. In kindergarten, we assessed children's (N=178) basic number skills, linguistic skills, and visual attention. In…