: In this paper we investigated the role of motor-manipulatory behaviour in the learning modalities of thirty-five primary school children interacting with a Lego MindStorms kit. In particular, by means of an observational taxonomy of children's behaviour, we analysed the video records of two observational sessions regarding the learning activities during the building of a small robot. Our results demonstrated that motormanipulatory behaviours are strictly linked to cognitive processes, and that the acquisition of new knowledge can be considered as the result of a gradual experience of integration between both perceptual and manipulative behavioural routines.