According to a poll from the National Alliance for Youth Sports, around 70 percent of kids in the United States stop playing organized sports by the age of 13 because “it’s just not fun anymore.” I have three kids, all of whom play sports, and my oldest is about to turn 13. I may not have understood why this was happening a few years ago, but sadly, knowing what I know now, the mass exodus of 13-year-olds from organized sports makes perfect sense to me.