Most have heard of the famous Stanford marshmallow experiment. In 1970, psychologist Walter Mischel invited kids into his lab. A child was offered a marshmallow that they could eat, or, if they waited until the researcher returned, they were given a second marshmallow. About one-third of the kids waited approximately fifteen minutes for the additional reward.
The study then tracked those children over time and found that children who waited for the second reward tended to have higher SAT scores and lower body mass indexes. Later tests have challenged those outcomes, but it hasn’t stopped parents everywhere from running the experiment on their kids, often with humorous results.