The risk is that there is 'no risk': a simple, innovative intervention to increase children's activity levels

School playgrounds offer everyday opportunities for physically active and social play that combats obesity, develops skills, and promotes well-being. However, teachers' fear of the legal consequences of injury can elicit over-zealous risk reduction with the result that playgrounds lack challenge, and the potential benefits of play become limited. In this research, we trialled a simple, cost-effective strategy to encourage children to be more active and social on a school playground. Over 11 weeks, we made available materials with no fixed purpose (e.g. car tires, boxes) to a playground of children aged five to seven. Accelerometers showed children became significantly more active. Interviews with teachers suggested children also became more social, creative, and resilient. However, despite no incidence of injuries, teachers perceived an increased risk and encountered dilemmas regarding duty of care. We conclude that future interventions should address issues of 'surplus safety' at individual, school, system, and policy levels.