The current study examined the dynamic and complex interplay among executive functions, visual-spatial skills, and mathematical achievement in primary school students. In particular, we investigated the bidirectional, longitudinal associations among these abilities, with executive functions consisting of working memory, inhibition, and cognitive flexibility. We examined 6- to 7-year-olds (N = 182) at the beginning of primary school and again 3 years later using the Intelligence and Development Scales-2. A cross-lagged panel model identified asymmetrical patterns in the data. Early visual-spatial skills predicted children’s later mathematical achievement; however, working memory predictions of later mathematical achievement depended on the time differences between assessments. Children with higher initial working memory skills showed accelerated gains in mathematical performance when the time difference between assessments was large. Importantly, early mathematical achievement predicted changes in later working memory, pointing to a bidirectional relation between working memory and mathematical achievement.