The premiere book in the STEM for Our Youngest Learners Series introduces the Infant Toddler Inquiry Learning Model, a new way to think about how young children (birth-age 3) explore, think, and learn STEM concepts. The book also demonstrates how the Inquiry Teaching Model can guide teachers in implementing STEM experiences for this age group. Accessible to educators from a wide range of educational backgrounds, this resource is designed specifically to help guide the integration of STEM experiences into the early childhood curriculum. Readers will see how the model works in real life; how STEM topics can be naturally embedded in daily routines and activities; and how to observe, understand, and interact with children as they explore. This accessible guide presents content and pedagogy aligned with what is known about how children learn and also addresses the challenges educators encounter when implementing STEM with infants and toddlers. Each volume in this new series includes vignettes showing educators and children engaging in inquiry learning, guidance for selecting materials and arranging the learning environment, modifications and accommodations for diverse learners, support for establishing adult learning communities to support professional development, and more. This book: (1) offers an easy-to-use model of infant and toddler inquiry-based learning focused on how young children engage, explore, and gain understanding of STEM concepts; (2) provides usable curriculum ideas for educators who may lack education or experience with infants and toddlers; (3) explores how young children learn and how educators can support them in the process; and (4) includes actual experiences and anecdotes from a variety of childcare settings. [This book was written with Rosemary Geiken, Jill Uhlenberg, and Sonia Yoshizawa.]