At Stanford University, students take part in the "Wacky Walk" before their commencement ceremony.China News Service / Getty

An astonishing number of students start college in America without finishing it: Roughly 40 percent of college enrollees don’t go on to get a degree within six years of starting to work toward one.

The good news is that in recent decades things have gotten a bit less bad. By one calculation, at four-year state schools that didn’t make the top 50 public universities in U.S. News & World Report’s rankings, the graduation rate within six years rose from about 40 percent for students starting in the early 1990s to about 50 percent for students starting in the late 2000s. (The phenomenon was not limited to non-elite schools.)

When Jeff Denning, an economist at Brigham Young University, started looking closely at the data on college-completion rates, he was a bit perplexed by what, exactly, was driving this uptick. He and some of his BYU colleagues noticed that a range of indicators from those two decades pointed in the direction of lower, not higher, graduation rates: More historically underrepresented groups of students (who tend to have lower graduation rates) were enrolling, students appeared to be studying less and spending more time working outside of school, and student-to-faculty ratios weren’t decreasing. “We started thinking, What could possibly explain this increase?” Denning told me. “Because we were stuck with not being able to explain anything.”

Stuck, that is, until they started looking at what was happening with students’ GPAs. Despite the aforementioned trends among the college-going population, students were, on average, earning higher grades in their first year of college. “[GPAs are] going up, and as best we can tell, there’s not a good reason that they’re going up, in terms of student behavior or preparation or anything like that,” Denning said.

If grades are improving but there’s no reason to think that students have become better students, an interesting possibility is raised: The unassuming, academic way Denning puts it in a recent paper (co-authored with his BYU colleague Eric Eide and Merrill Warnick, an incoming Stanford doctoral student) is that “standards for degree receipt” may have changed. A less measured way of saying what that implies: College may have gotten easier.

Christina Ciocca Eller, a sociologist at Harvard who studies higher education, and who wasn’t involved with Denning’s research, points out that “easier” could mean a couple of different things. College could have gotten easier in the sense that it presents students with simpler material than before, or in the sense that it presents students with similar material as in the past but grades them more forgivingly. “I actually think that the latter explanation, about grade inflation, is more plausible,” Ciocca Eller told me, though she also noted that the college-has-gotten-easier hypothesis is not definitive.

Denning himself noted this, too. He called the paper, which hasn’t yet been published in a peer-reviewed academic journal, “a first stab”—an exploration of a question he welcomes other researchers to look into. It could well be the case, he said, that “schools are just better at helping students” than they used to be. Indeed, many colleges have launched initiatives to help more students graduate, but the effectiveness of these programs varies, and Denning said he does not have specific-enough data to analyze their role in rising graduation rates nationwide.

Whatever is responsible for the increase, it seems to serve the needs of colleges and universities, especially public ones. Lately, Ciocca Eller said, schools are being held more accountable for their graduation rates, with some states tying educational funding to certain statistical benchmarks. “Potentially, there’s pressure on faculty to help students, especially underprepared students, to move them through the curriculum in order to keep churning up the graduation rate,” she said.

Denning and his co-authors acknowledged this possibility, noting in their paper that altering what’s necessary to get a degree is “the lowest cost way to increase graduation rates.” But colleges’ widespread use of this tactic, conscious or not, is at this point just guessed at and far from proven.

Indeed, the underlying cause of this graduation-rate increase is a mystery. David Kirp, a professor at UC Berkeley and the author of the forthcoming book The College Dropout Scandal, says that there are a bunch of different possible explanations for it. Maybe college has indeed gotten easier. But maybe high schools are churning out better-prepared graduates, and students have started arriving on campus more ready for the material. At this point, Kirp wrote in an email, “we just don’t know.”

One knock on the getting-easier theory, he said, is that colleges that let in similar types of students can have significantly different graduation rates—which could indicate that an individual school’s student-support initiatives matter, or at least that higher education isn’t getting less rigorous in any uniform manner. “My strong hunch is that multiple factors are operating here,” Kirp wrote to me.

Ciocca Eller noted some other caveats. For one, she’d like to see researchers examine the role of other, more granular variables than the ones Denning and his co-authors looked at; in her eyes, their analysis doesn’t present “a full picture.” She also cautioned that focusing on aggregate statistics can hide the often stark disparities among students with different racial and socioeconomic backgrounds. Perhaps studying particular groups of students would be more fruitful than taking a broad view.

But the mere fact that researchers aren’t sure about all this raises a larger question of how difficult college is, or should be. “I think people interpret this as a really bad thing, or at least, if college is easier, that’s a failure,” Denning said of his paper’s suggestion. “And it’s not at all clear to me that that’s true.” Maybe college is too hard, and should be made easier. Maybe the opposite is true. Either way, Denning likes to think about difficulty as something that isn’t fixed and that can be purposefully tweaked. “You can pick what the grade distribution looks like at your university or your department … and those will have effects on stuff that we care about, like graduation [rates],” he said. Colleges, in other words, get to decide what it means to be deserving of a degree.

Of course, there are other ways to improve graduation rates. Ciocca Eller listed a number of them: dedicated, individualized advising early on that helps undecided students learn about the various pathways open to them. Dedicated, individualized advising later on that helps them with challenges specific to their major or track. Credit-bearing academic-support programs that help students who are struggling. Setting up cohorts of students at commuter schools who can help one another out when, say, one of them has to miss a class. Giving low-income students some money to help pay for textbooks and transportation.

“We know so much about what works—like so, so, so, much—that it’s just absolutely shocking to me sometimes how long it takes even to implement the lowest-hanging fruit,” Ciocca Eller said.

Kirp, too, lists fixes in his upcoming book, such as modifying remedial classes that many students fail and helping promising low-income students find better-resourced schools that they might not have considered attainable. These things would take some work, but they’d effect meaningful change, helping more students graduate—whether doing so is easier or not.

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