This study investigates the learning exchange between three- to six-year-old children and their grandparents, in Sylheti/Bengali-speaking families of Bangladeshi origin and monolingual English-speaking families living in east London. The following concepts from sociocultural theory are applied to this new area of intergenerational learning: "scaffolding", "synergy" leading to mutual benefits for the young child and their caregiver, "syncretizing" of knowledge from different sources, "funds of knowledge" within communities, and the transmission of knowledge or "prolepsis" between generations. Methods include an initial survey at a primary school to establish the range of learning activities taking place at home between grandparents and children, followed by case studies of nine families through interviews, video-recording and scrapbooks. Qualitative analysis of the data reveals how learning interactions are co-constructed by children and grandparents within a relationship of mutuality in which touch is a particularly significant mode of communication. The intergenerational exchange develops concepts and skills that complement children's school learning, and involves cultural continuity as well as change. (Contains 3 figures, 2 tables, and 1 note.)