Classic moral stories have been used for centuries to teach children the virtue of honesty, but there hasn’t been any scientific evidence that they work — until now:
This study compared the effectiveness of four classic moral stories in promoting honesty in 3- to 7-year-olds. Surprisingly, the stories of “Pinocchio” and “The Boy Who Cried Wolf” failed to reduce lying in children. In contrast, the apocryphal story of “George Washington and the Cherry Tree” significantly increased truth telling. Further results suggest that the reason for the difference in honesty-promoting effectiveness between the “George Washington” story and the other stories was that the former emphasizes the positive consequences of honesty, whereas the latter focus on the negative consequences of dishonesty. When the “George Washington” story was altered to focus on the negative consequences of dishonesty, it too failed to promote honesty in children.
(Hat tip to Tyler Cowen.)