We present a field experiment to study the effects of non-monetary incentives on healthy food choices of 282 children in elementary schools. Previous interventions have typically paid participants for healthy eating, but this often may not be feasible. We introduce a system where food items are...

Understanding the roots of human cooperation among strangers is of great importance for solving pressing social dilemmas and maintening public goods in human societies. We study the development of cooperation in 929 young children, aged 3 to 6. In a unified experimental framework, we examine...