While summer employment used to be the norm for America’s youth, young people today are attending summer classes and engaging in a variety of extracurricular activities, rather than working. In the summer of 2018, only 40% of U.S. teens were participants in the labor market; in 1980, nearly 70% of teens held summer jobs. It does seem that summer courses are a significant factor in teens’ decision not to work, as the percentage of teens enrolled in summer classes has increased from 10% in 1980 to 45% in 2018. As employers seek to fill open positions, they are beginning to target older demographics with their recruitment efforts.
See "Businesses are struggling with a new labor problem: Fewer teens have time for summer jobs", Kate Rogers & Nick Wells, CNBC, July 5, 2019