They can and will: Preschoolers encourage pro-environmental behavior with rewards and punishments

Studies have shown that young children can think pro-environmentally, however, whether they can act pro-environmentally even at a personal cost remains unknown. We directly investigated how 4–6-year-old preschoolers reacted to pro-environmental and anti-environmental behaviors within their sphere of influence. In two studies (N = 211), children were presented with vignettes, which showed both pro-environmental and anti-environmental actions, and completed three tasks: distributed stickers (reward) to the protagonists shown in the vignettes (Task I) and distributed either non-costly (Task II) or costly (Task III) unpleasant items (punishment) to the protagonists. Results showed that older children rewarded pro-environmental actions more than younger children. Furthermore, 4–6-year-olds consistently punished anti-environmental actions. Moreover, 6-year-olds (but not younger children) systematically reasoned and insisted on punishment even at a personal sacrifice. Together, preschoolers acted pro-environmentally, suggesting that from early in development, preschoolers show a behavioral capacity and willingness to encourage pro-environmental behaviors.