Michael Gamez, 22, has wanted to work on cars since he was a kid, just like his father and grandfather. He fixed up and sold his first used car when he was 14. "It felt really good to build something up and sell it for a profit," says Gamez.

But his teachers conditioned him to equate a college degree with success. So he enrolled at the University of California, Irvine, with a plan to major in mechanical engineering. During his sophomore year, Gamez dropped out because he realized that he was on the wrong path.

Sen. Bernie Sanders (I–Vt.)and Sen. Elizabeth Warren (D–Mass.) have promised that, if elected, they'll make public college tuition-free and wipe clear federal student loan debt, which in the U.S. tops $1.5 trillion. Their claim is that making college universal will lead to higher productivity and more economic opportunity for people like Gamez.

"If you make college free, then there's going to be so many [degrees] floating around that if you want to get a better job, then you're going to need to go and get some supplemental degree," says Bryan Caplan, an economist at George Mason University and author of The Case Against Education. He's skeptical that professors like him have much to offer most students.

"We're spending too much time and money on education because most of what you learn in school you will never use after the final exam," says Caplan. "If you just calmly compare what we're studying to what we really do, the connection is shockingly weak."

Caplan says that most people attend college as a way to signal to prospective employers that they're reasonably intelligent, conscientious, and conformist.

"The signaling story is mostly that our society says that you're supposed to graduate, and if you're supposed to graduate, the failure to graduate signals non-conformity," says Caplan. "People that are willing to just bite their tongues and suffer through it are the ones who are also going to be good at doing that once they get a job."

Caplan's case rests partly on the so-called sheepskin effect, named for the material on which diplomas were once printed.

Studies of the earnings of college graduates reveal that the average salary increase for completing the last year of college is on average more than double that of completing the first three, implying that it's the fortitude to obtain the degree—not the knowledge gained—that explains the boost in compensation.

"The usual view, called the human capital view, says that basically all of what's going on in schools, is that they are pouring useful skills into you," says Caplan. "What I'm saying is the main payoff you're getting from school is that you're getting certified, you're getting stamped. You are, in other words, getting what you need to convince employers that you are a good bet."

Instead of college, Leah Wilczewski, 21, enrolled in Praxis, a one-year job skills program focusing on communication, marketing, and other jobs. It cost $12,000 but included a 6-month paid apprenticeship worth $16,000, meaning she'll finish the program $4,000 in the black.

Wilczewski is in the middle of her apprenticeship at Impossible Foods, the Bay Area company that sells a meatless hamburger.

"I feel as if being in Praxis and being able to nail a job that typically requires four years of school, if not more…it's like, okay, with that knowledge, what else can I do?" says Wilczewski.

After Michael Gamez dropped out of UC Irvine, he enrolled in an auto mechanic trade school while also working at Pep Boys. Then he applied for and received a $12,400 scholarship from Mike Rowe Works, which helps young people looking to enter the skilled trades

From there, he entered a three-month training program with BMW and a day after finishing began his job as a high-level technician at BMW of Beverly Hills.

"Now that I work with cars…I get excited to go to work," says Gamez. "I feel like a lot of people, they get surprised when I tell them the amount of money that a mechanic or a technician can make at a dealership."

Even though it's possible to acquire the necessary skills to make a good living without attending college, enrollment at 4-year universities has stayed steady for the past 10 years, and an Economics of Education Review study by Nicholas Turner found that every dollar of federal aid spending crowds out about 83 cents of institutional aid. Such trends leave Caplan skeptical that enrollment will fall anytime soon despite the increasing availability of online alternatives.

"If you've got that kind of guaranteed customer base where the taxpayers have no choice in whether or not the money's going to be spent and the government hands it over to you, then you're going to be fine," says Caplan.

As for Wilczewski, she has two more months left in her apprenticeship and is hopeful that Impossible Foods will keep her on in the sales department. Gamez hopes that working for BMW is a first step towards eventually owning his own shop.

Produced by Zach Weissmueller. Camera by John Osterhoudt, Alexis Garcia, Jim Epstein, Todd Krainin, and Weissmueller.

Photo credits: Anthony Behar/Sipa USA/Newscom, Bastiaan Slabbers/ZUMA Press/Newscom, Jack Kurtz/ZUMA Press/Newscom.

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