Development of numerical relational and counting skills as components of early numeracy

Background: Longitudinal data on the development of early numeracy components are scarce, yet essential for understanding how these skills emerge and how to support them. Aims: This study examined growth trajectories of numerical relational and counting skills as early numeracy components to assess developmental interdependencies. Sample: A cohort-sequential design provided longitudinal data (two to six measurements) of Dutch children between mid-Kindergarten year 1 and the end of Grade 1 (ages 4 to 7). Analyses covered a population sample (N = 1252) and a subsample (N = 414) with at-risk (low-performing) and typically developing learners. Methods: Using the Dutch Early Numeracy Test-3, univariate and multivariate latent growth curve models were fit, followed by multigroup analyses comparing typically developing and at-risk learners. Results: In the population sample, numerical relational and counting skills both developed nonlinearly, with numerical relational skills decelerating and counting skills accelerating towards the end of Grade 1 without reaching ceiling. Results suggest numerical relational skills may precede counting skills, with initial levels and growth in numerical relational skills contributing to counting skill development. Typically developing children showed similar patterns, but counting skill growth also decelerated. At-risk learners displayed lower initial levels and delayed growth, especially in counting skills. Additionally, the interdependence between numerical relational and counting skills was weaker in at-risk learners. Conclusions: Findings show absence of ceiling effects on both components at the end of Grade 1, despite overall growth. At-risk children showed lower initial levels, delayed growth, and weaker dependency between core components, resulting in persistent lags.