The development of (non-)symbolic comparison skills throughout kindergarten and their relations with basic mathematical skills

• Comparison skills of 671 children were assessed at six time points within 2.5 years.
• Non-symbolic and symbolic comparison skills influence each other reciprocally.
• Symbolic comparison skills contribute most to basic math achievement.

Although numerical skills have proven to be important precursors for mathematical proficiency, longitudinal studies on numerical development are rather scarce. The overall goal of the present study is to gain insight in numerical skills, that is non-symbolic and symbolic comparison skills, as precursors of mapping skills and basic math achievement of children within a longitudinal design. Over two and a half years, 671 kindergartners (mean age 4.6 years at the start of the study) were assessed on non-symbolic and symbolic comparison skills at six time points, and on their basic math achievement (divided into math fluency and math reasoning), and mapping skills at the end of first grade. Multivariate latent growth curve models show an interrelation between (the development of) non-symbolic and symbolic comparison skills. Results furthermore reveal symbolic comparison skills as the most important predictor of mapping skills and basic math achievement. Growth in non-symbolic comparison skills predicted math fluency in first grade.