Computational thinking is central to many science, technology, engineering, and mathematics (STEM) careers of the future, yet many young children do not have opportunities to develop the computational thinking (CT) skills that lay the foundation for future STEM trajectories leading to these careers. This project will address this opportunity gap through developing and researching a story-based approach to fostering computational thinking among young children. As part of this approach, in the context of stories, children will use discovery-based tinkering activities to develop solutions to problems using computational thinking. While children will initially use this "tinker-telling" approach in the context of libraries and museums, the project will provide professional learning materials and opportunities to informal educators in these settings on how they can, in turn, support caregivers in extending the tinker-telling approach to computational thinking using stories and everyday materials in their homes. The project team, informal educators, and caregivers will iteratively co-design, test, and refine a guidebook, which will highlight how to teach computational thinking through playful story-based tinkering in museums, libraries, and homes. Research will explore whether and how the professional learning experiences, and the use of the guidebook, increase children's computational thinking skills and dispositions, as well as promote caregivers' sense of confidence in supporti