Children attending centre-based early childhood care and education programmes across Australia are most likely to be grouped according to age and development. While multi- or mixed-age grouping has been seen to have positive benefits on young children's learning and pro-social behaviours, this approach is not usually adopted in the organisation of children's grouping in most long day care settings across the county. This paper reports on a case study which explored one urban children's setting where the outdoor learning space has been specifically designed to enable a mixed-age approach for children. The findings suggest that while the educators see many benefits across the age groups in engaging in this approach, there is still a preference to segregate the very young children arising from concerns for their safety. The study also found that planning for learning especially in regards pro-social learning with the older children has been problematic. (author abstract)