This paper develops a set of design strategies for promoting young children’s physical activity. These strategies are developed by taking the design perspective of Playscapes as a starting point. Playscapes suggests that three play qualities are key in promoting young children’s physical activity: free, bodily, and dispersed play. We present two field studies in a pediatric oncology center, in which we observed how these play qualities were reflected in children’s interactions with two Playscape designs: Stickz, a collection of branch-shaped objects, were placed in a semi-public waiting area; Fizzy, a self-propelled robotic ball, was introduced to patient rooms. Free play was analyzed according to the diversity of play activities, bodily play according to the diversity and exertion level of bodily movements, and dispersed play according to the floor area covered. Based on the findings, we discuss how Fizzy and Stickz contributed to each play quality, and derive a set of design strategies that can be applied in different contexts to stimulate young children’s physical activity. With these strategies, Playscapes offers a concrete alternative to existing approaches, supporting designers in directing interactions towards physical activity while leaving room for children’s unstructured and spontaneous play.