Examining the malleability of young children's flexible attention to numerical and spatial magnitudes.

Math ability is critical to children's future school and career success, and prior studies show that flexible attention to magnitudes (FAM) predicts children's future math abilities over and above other early math skills. FAM broadly refers to the ability to switch flexibly between attending to different dimensions of magnitude (e.g., size and numerosity). In the current study, we created an intervention using number books to test, for the first time, the malleability of children's FAM ability. A randomized experiment was conducted with 116 preschool-age children (Mage = 55.6 months; 54.3 % female) to test our hypothesis that FAM ability is malleable and can be trained using number books. The intervention included four conditions to which children were randomly assigned: size-to-number, mixed, conventional counting, and non-numerical. The experimental conditions were size-to-number and mixed, while the conventional counting and non-numerical conditions served as controls. Consistent with our hypothesis, children significantly improved in FAM task performance from pre- to post-intervention within the experimental groups, but not within the control groups. Furthermore, children in the two experimental conditions combined significantly improved number line estimation scores from pre- to post-intervention, unlike the combined two control conditions. Implications of these findings on the development of future FAM interventions are discussed.