Your grandparents probably told you a thousand stories about working at drive-ins and lifeguarding at the city pool during their summers off from school.

Your parents likely worked for extra cash over breaks, too. But if you're a young person today, that might not be the case.

Pew Research Center revealed last year that the number of teens upholding the all-American tradition of getting a summer job has been steadily declining for the past two decades. Even the minority of millennials who did spend their summer holidays punching the clock have had very different roles than their parents and their parents did during the 20th century.

Based on employment-population ratios from the Bureau of Labor Statistics , the average number of 16- to 19-year-olds who were employed over the summer historically lingered around 50%, rarely dipping below that mark before the millennium.

But that number hit its lowest point of 30% in 2008, amidst the Great Recession, and has only slightly begun to increase since then, the Pew study showed .

Still, though, only about a third of teens take up summer jobs nowadays.

And there are several reasons for that change. Here are four of the biggest ways summer jobs have changed over the years.

The rise of internship culture

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It's no secret that the nature of summer work has shifted tremendously since Baby Boomers held summer jobs.

The stagnant unemployment rate reported by the Bureau of Labor Statistics in April proves that the labor market is tight and not loosening up anytime soon. Students are starting their careers at a younger age with summer internships instead of scooping soft serve at the local ice cream shop.

Read more: Inside Under Armour's exclusive internship program, which is harder to get into than Harvard

A 2014 Millennial Branding report revealed that more than half the students surveyed said they felt pressured by their parents to get professional experience during high school, ultimately leading to increased interest in summer internships, fellowships, and career-driven volunteer opportunities.

The automation revolution

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Believe it or not, the likelihood of a robot taking your kid's future summer job is pretty high.

According to a recent report from the Organisation for Economic Co-operation and Development, low-wage, entry-level positions are the first to be compromised by the rise of artificial intelligence.

"A striking novel finding is that the risk of automation is the highest among teenage jobs ," the study said. "The relationship between automation and age is U-shaped, but the peak in automatability among youth jobs is far more pronounced than the peak among senior workers."

Generational attitudes

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Plain and simple: Some adolescents just don't want to work.

Call it laziness, entitlement, or whatever you want, but The Atlantic says that many of today's teenagers are foregoing their summer paychecks for something even more productive.

Read more: Amazon has so many summer interns, it costs $4.4 million to feed and house them and Seattle has to add extra city buses

According to the Bureau of Labor Statistics, summer school enrollment for this same age group has tripled in the past 20 years, and started increasing around the same time teen employment started going down. Similar to the trend in high schoolers taking up internships, it seems a hefty portion of Generation Z is actually willing to trade spending money for a better education these days.

Employment habits

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Even if today's teens wanted to flip burgers at the diner like their grandparents did, many of those romanticized summer jobs aren't even available anymore.

The 2018 Teen Summer Job Report from Challenger, Gray & Christmas showed that hiring of 16- to 19-year-olds fell a whole 4% in 2017. Andrew Challenger, Vice President of the executive outplacement firm, said it could be because so many big-name retailers (Toys R Us, for instance) are going out of business.

Another challenge for youth workers is, according to data from the Center of Economic and Policy Research , competing with an older generation. The fast food industry that once hired out entire high schools over the summer now employ twice as many 20- to 54-year-olds as teens.

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