PROJECT SUMMARY/ABSTRACT Spatial ability encompasses the ability to understand size, shape, location, direction and distance, to reorient/navigate in space, to use maps/diagrams, to mentally rotate objects, and to recreate patterns. Spatial abilities can be categorized as intrinsic or extrinsic. Intrinsic spatial ability involves understanding the relations within an object or between an object’s constituent parts. Extrinsic spatial thinking involves understanding the relations between two or more objects or between an object and its environment. Spatial skills predict children’s early math and science achievement, and later entry and success in Science, Technology, Engineering, and Mathematics (STEM) disciplines. The identification of factors that predict individual differences in spatial thinking is important because since spatial thinking is malleable, we can use this information to develop evidence-based interventions to improve STEM learning. Little research exists on the influence of parent characteristics in explaining individual differences in children’s spatial thinking, despite theoretical motivation to investigate this relation. This project aims to examine whether, and to what extent, parent characteristics, including their spatial ability, STEM interest, and spatial anxiety, directly and indirectly via parent toy preference and frequency of parent-child engagement in spatial activities at home, predict individual differences in children’s intrinsic (i.e., mental rotation) and extrinsic spatial ability (i.e., spatial scaling). A total of 150 parent-child dyads (children aged 4-6 years) will be recruited through various social media platforms. This study will be conducted remotely via a one-hour zoom video call with a trained experimenter. Parents will be asked questions about their demographics, STEM interest, spatial anxiety, spatial activities at home, and toy preferences for their child. Intrinsic (mental rotation) and extrinsic (spatial scaling) spatial tasks that have been adapted for remote administration will be given separately to parent and child. Structural equational modeling will be used to evaluate the direct and indirect effects of parent characteristics on children’s spatial ability.