Research on gesture development has mostly focused on home environments. Little is known about early communicative development in other relevant contexts, such as early-year-schools. These settings, rich in diverse educative situations, objects, and communicative partners, provide a contrast to parent-child interactions, complementing our understanding of gesture development. This study aims to describe the development of the first gestures in the infant classrooms of early-years-schools, focusing on ostensive gestures of showing and giving-their emergence, communicative functions, and relation to the subsequent emergence of pointing. We conducted a longitudinal, observational investigation analyzing the gestures of 21 children (7-13 months). Over 7 months, we observed and registered children's daily interactions in the classroom, employing a mixed quantitative and qualitative approach to analyze the types and functions of their gestures. We found a significant increase and diversification of gesture types and functions with age. Gestures followed a proximal-distal developmental course. Ostensive gestures were the earliest and most prevalent gestures observed. There was a correlation between the frequency of these gestures, with ostensive gestures fulfilling communicative functions later observed in pointing. Our qualitative analysis revealed the progressive construction of ostensive gestures into spontaneous, complex, and conventional forms of communication. These results highlight the important role of ostensive gestures in early communicative development, paving the way for distal communication through pointing and relating to the origin of intentional communication. More broadly, these findings have significant implications for early educational practices and show the value of conducting research on developmental processes in early education.