Abstract
Children aged 3-5 ys of a nursery school were videorecorded while performing unstructured games for 30 min in an empty playroom. Each group was exposed to different conditions where the only objects present in the room were circles spread on the floor or piled. In each condition movement we measured proportion of time spent by each child running and/or walking without object manipulation or standing with no activity. The motor behaviour of the children was homogeneous as no statistical difference was observed between groups. When circles were spread children spend most of their time running/walking will little or none manipulation; when circles were piled children used objects for manual and symbolic games throughout all the time. The data indicate that organization of playground modulates motor behaviour of children playing unstructured games, whereas selection of tools available to children and their mode of presentation influence the intensity of physical activity.