The computer is widely recognised as a cultural tool with the potential to enhance learning, and children are considered to develop ICT skills with particular facility. However, young children still require assistance in order to gain the maximum educational benefit. This study investigates how such assistance was given to 3-6 year olds by their grandparents in Sylheti/Bengali-speaking families and monolingual English-speaking families living in East London. A multimodal analysis of video-recorded computer activities reveals the reciprocity of teaching and learning taking place between the generations. In each case, grandparents and grandchildren combined their resources in order to negotiate the activity, with adults usually providing knowledge of literacy and numeracy whilst children helped with computer skills. The intergenerational exchange was especially evident in Sylheti/Bengali-speaking families, where grandparents were less familiar with English or with the computer and operated bilingually with their grandchildren to co-construct learning. However, the support offered by grandparents was found to have common elements in all families, as they helped children to structure the learning event, maintain concentration and accomplish tasks relying on linguistic and cultural knowledge.