“…We take an exploratory approach in this study given the mixed evidence on antecedents to low mathematical performance classification and that CART analyses are data-driven and exploratory by nature. However, given that specific mathematical skills and concepts develop in a connected and cumulative manner, called a learning Purpura, Day, Napoli, & Hart trajectory, and that these domain-specific and domain-general factors likely play a role in mathematical acquisition for more targeted components of mathematics development (Lan et al, 2011;Purpura & Napoli, 2015;Purpura, Schmitt, et al, 2017), we expected different factors to predict low mathematics performance for younger preschool children and older preschool children. Importantly, we are defining the classification outcomes as "low mathematical performance" rather than mathematical learning disabilities because of the exploratory nature of the study.…”