Child development involves the process of mastering cultural tools, which modify relations with the world and provide the means to act on the self. A sign is a universal cultural tool, but these tools are not the same for all ages. The problem of specifying development becomes one of finding the tools that children use in their activity. Capacities (as opposed to knowledge, skills or habits) have a meaning that lasts for life. One type of capacity is to find the qualities of the world using sign tools and modelling. A second type is to express attitudes to reality using symbolisation. Childhood activities provide a special space for the development of capacities. Researchers have identified two types of situations in which capacities develop. In the first, children learn to identify natural phenomena through observation and the use of sign tools (modelling). In the second, children use symbolic tools such as painting, dancing and stories to understand these phenomena and express their attitudes towards them (symbolisation). Regulation of children's actions happens in three ways. The first uses sign tools and involves the adoption of cultural standards. The second uses symbolic tools and involves expressing an attitude towards events. The third uses both sign and symbolic tools and involves transforming reality in a personally meaningful way. These three ways of regulation give rise to three types of cognitive capacity; normative, symbolic and transformational. Coaching children in the run-up to school entry results in predominantly "normative" capacities. The problem of giftedness is related to the problem of capacities. Giftedness is related to the development of capacities in preschool rather than to specific knowledge, skills or habits. This analysis solved the problem of intellectual and creative giftedness being poorly correlated, but raised the further problem of how to influence the development of giftedness. A total of 17 preschool children, 10 of whom were identified as intellectually gifted, were followed for two years. An intervention supported the mastery of figurative tools. The results of testing supported the analysis of "capacities" as underpinning the development of giftedness.