The premiere volume 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. Accessible to educators from a wide range of educational backgrounds, it is designed specifically to help guide the implementation 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, establishing adult learning communities to support professional development, and more.