Ella James-Brabham

By the time children begin formal schooling, substantial individual differences in their mathematics skills1 already exist (e.g., Blakey et al. 2020; Coolen et al. 2021; DeFlorio and Beliakoff 2015; Robinson and Lubienski 2011). These are remarkably stable, such that children who begin formal schooling behind their peers are likely to remain behind, with these differences widening over schooling (Aubrey et al. 2006; Aunio and Niemivirta 2010; Educational Endowment Foundation 2017).

HMA home mathematical activity PRISMA Preferred Reporting Items for Systematic Reviews and Meta-Analyses SES socioeconomic status Children's mathematical skills rapidly develop in the preschool years. However, attainment gaps are already visible by age 4 (Blakey et al., 2020; James-Brabham et al., 2023; Sirin, 2005).

Measures and procedure Children were tested individually, completing all seven tasks in a single 45-min session in their preschool. Tasks were administered in the following fixed order: Give-a-Number (cardinality), Black/White Stroop (inhibitory control), Object Span (working memory), Bubble Popping (processing speed), TEMA (standardized mathematical ability measure), Counting, and BPVS (verbal ability). Children were rewarded with stickers for completing the tasks.