From bagging groceries to scooping ice cream to delivering newspapers, summer jobs were a rite of passage for American teenagers. In 1978, 72 percent of Americans ages 16 to 19 were either working or looking for jobs. In 2016, only 43 percent of teenagers were active on the job market. So what happened? It’s not that teens are lazy, it’s that their priorities have changed: instead of making money, many are focused on summer classes, internships, and building their resumes for college. They’re