Mobilizing picture books: Multimodal practices of participation and socialization in Kindergarten read-aloud activities

• Teachers mobilize picture books through embodied actions, securing and sustaining joint attention. • Multimodal resources—gaze, gesture, and book positioning—configure and reconfigure participation frameworks. • Picture books function as manipulable focal objects that index shifts in activity and order. • Participation is organized to alternate between narrative engagement and everyday instruction, shaping children’s conduct. • The study demonstrates how material resources mediate participation and socialization in early childhood education. This study investigates how picture books, as material resources mobilized by teachers, organize participation and mediate socialization during read-aloud activities in Japanese kindergartens. Drawing on ethnomethodology and multimodal conversation analysis, it examines video-recorded sessions of three-year-old children in their first month of kindergarten. The analysis shows that teachers’ embodied practices—such as holding, pointing to, angling, and lowering the picture book—are crucial in establishing joint attention, guiding intersubjectivity, and managing classroom order. Picture books function not only as gateways to the narrative world but also as mobilized objects that index the state of activity: story progression, suspension, or rule enforcement. Teachers navigate seamlessly between narrative delivery and real-world instruction (e.g., toilet use, behavioral norms), using the book as a pivot to integrate storytelling with socialization into classroom routines. By situating these findings within research on joint attention, mobilized objects, and instructional transitions, the study demonstrates that read-aloud sessions are not merely opportunities for transmitting stories but are dynamic, interactionally organized environments where institutional norms are accomplished through material and embodied practices.