Do preschool cognitive and executive function skills explain the school readiness gap between socioeconomically advantaged and disadvantaged South African children?

To ensure that all children can fulfill their potential, it is essential to examine the factors underlying poverty-related achievement gaps. Executive function (EF) skills, foundational to learning, have been shown to mediate the relationship between socio-economic status (SES) and academic performance, yet evidence from South Africa remains limited. This study investigates the extent to which EF explains disparities in academic outcomes among South African preschool children. Using the national Thrive by Five Index 2021 dataset (N = 5,222), children were grouped by preschool quintile as a proxy for SES. Outcomes were measured using the Early Learning Outcomes Measure (ELOM) 4&5, focusing on Numeracy and Mathematics (ENM) and Cognition and Executive Functioning (CEF). SES was significantly associated with both CEF and ENM, which were strongly correlated. Hierarchical regression showed that adding CEF improved model fit, explaining 32% of the variance in ENM. Multilevel mediation indicated a significant indirect effect of SES on ENM via CEF, with no direct effect. Findings highlight EF as a key mechanism linking SES to numeracy, supporting EF-targeted interventions to reduce educational inequality