To achieve multiple learning objectives, the ideal preschool activity center should promote development across all domains, from adaptive to social-communicative. Though early childhood practitioners describe the sensory table as capable of doing so, empirical accounts stand in stark contrast and suggest that it is a non-social functional activity. The intent of the present investigation was to reconcile this distinct dichotomy through the systematic manipulation of four sensory table substances (sand, soil, rocks, and water) and provision sets that differed in realism to determine their effect on preschoolers' free play behavior. Preschoolers' play forms and social participation were observed at the sensory table as they used a novel surface, which was introduced weekly without repetition, and either a set of minimally structured objects or realistic toys. Preschoolers' play and social participation were indeed influenced by the arrangement of the table. The sand, water, and provision sets yielded the most salient effects. Sand pulled for more sophisticated cognitive and social play forms while water pulled for more rudimentary ones. Regarding provision sets, the highly structured toys pulled for the most mature cognitive play form while the minimally structured toys pulled for the most sophisticated social context. The highly structured toys, with realism that lent to specific themes, appear to have functioned as a thematic anchor and cultivated a greater occurrence of dramatic play as compared to the minimally structured objects, which pulled for more functional play. Conversely, the minimally structured toy set, containing objects that loosely represented realistic objects and/or were capable of multiple functions, fostered a greater amount of socialization through parallel, social, and social-constructive play. Aside from its motoric and adaptive value, findings from this investigation suggest that under certain ecological conditions the sensory table fosters the development of cognitive and social skills. Recommendations for early childhood education practitioners are provided.