This volume offers a comprehensible and insightful analysis of key factors shaping childrens additional language learning in instructional settings. With its thoughtful exploration of childrens oral and written development, the role of instruction, affective and social factors as well as digital technology, the volume provides invaluable guidance for researchers and educators. A must-read for anyone devoted to fostering childrens success in additional language learning. * María del Pilar García Mayo, University of the Basque Country, Spain * In this veritable tour de force, Yuko Goto Butler presents an all-embracing, compelling overview of childrens additional language development. In her characteristically meticulous style, she connects research to pedagogy, imparts invaluable insights, advocates for a child-centered approach to research and considers multilingualism, diversity, and variability in childrens language development. This is an essential resource for academic courses, challenging us all to boldly go where no one has gone before! * Sandie Mourão, Nova University of Lisbon, Portugal * This insightful book bridges theory and practice to explore how children learn additional languages in instructional settings. With a learner-centred approach, it champions multilingualism, diversity, and ecological perspectives essential reading for educators, researchers, and policymakers committed to understanding and supporting language development in young learners. * Victoria A. Murphy, University of Oxford, UK *