WestEd conducted a classroom-based study for the CPB-PBS Ready To Learn Initiative during the summer of 2014 in order to investigate children's relatively unmediated use of the Curious George's Busy Day transmedia suite in supporting preschool children's mathematics learning in the classroom environment. The Curious George's Busy Day transmedia suite includes digital games, hands-on learning activities, and video episodes, all featuring Curious George. The suite uses a narrative domain throughout all aspects of its education products and media platforms to engage children and support learning around the mathematics concept of numeracy. The current study explored the effectiveness of the Curious George's Busy Day transmedia suite in supporting preschool children's mathematics learning in the preschool classroom environment. In addition, the study examined the affordances (features and advantages) of transmedia-based learning in the preschool classroom. The study included an intervention developed by teachers and researchers that included all aspects of the suite (digital games, hands-on learning activities, and video episodes) and allowed for a relatively unmediated blended learning experience that was integrated into a typical preschool curriculum. The research questions guiding this study were: 1) Does children's self-directed use of the Curious George's Busy Day transmedia suite in the preschool classroom lead to gains in preschool children's early mathematical knowledge in the domains of "Numbers and Counting" and "Operations"? 2) What are the affordances of the use of the Curious George's Busy Day transmedia suite and related education materials in the preschool classroom? (author abstract)