NEW YORK — President Barack Obama's efforts to increase the percentage of Americans with college degrees is running into some of the same stubborn obstacles that have stymied educators, politicians, researchers and philanthropic foundations for years.

While a few efforts have succeeded in identifying barriers to graduation, research shows that they have yet to bring widespread improvement.

Achieving the Dream, a national nonprofit dedicated to helping more community college students succeed, began seven years ago with pilot programs at 26 community colleges, and has since expanded to 160. The program has cost more than $76 million, but a review released in February by the social policy organization MDRC found there has been no increase in graduation rates as a result.

"We have not found any magic bullets," says Thomas Brock, MDRC's director of policy for postsecondary education. "The budget-cutting and the difficulty students are having getting into classes — those are pushing back against the goal."

Carol Lincoln, Achieving the Dream's senior vice president, concedes that raising graduation rates "is like turning a 700-ton ship. People expect quick fixes. But we're talking decades in terms of significant results across the board."

The graduation problem isn't generally evident at elite colleges and universities, both private and public, whose graduation rates are comparatively high. It's concentrated at community colleges and lower-tier public universities, which enroll most of America's students. Such institutions increasingly serve the fastest-growing segment of American college enrollment: low-income, nonwhite, non-native-English-speaking students who are the first in their families to go to college.

Community colleges enroll much higher percentages of students who work full or part time and are considered at risk for dropping out — and who also are more likely to have children at home and have interrupted their education, in some cases for years.

In addition, the vast majority arrives unprepared for college-level work, with 60 percent or more steered into remedial education, according to Thomas Bailey, director of the Community College Research Center at Teachers College, Columbia University.

"They don't have money, they're working, they're the people who are least likely to afford the tuition increases," says Stan Jones, president of Complete College America, a national nonprofit working to increase the number of Americans with a college degree or credential. "We have a lot of work to do so that we don't fail them."

Community colleges will have to "engage in broad institutional reform" to increase the number of students who earn degrees and certificates, according to a series of papers published this year by the Community College Research Center.

Improving graduation rates, says Brock of MDRC, remains "a long-term process. A lot of colleges have made small changes, mostly as pilot programs, to come up with better strategies for serving students, but what has been lacking is really systemic change."

Still, says Brock, "there is momentum. A lot of institutions are focused now on this."

Here's a look at some recent efforts:

• The City University of New York waives tuition for needy students, gives them free subway passes and textbooks, and ensures smaller classes. It requires full-time study and provides advisers and career counselors to improve completion rates. In a pilot program involving some 300 students in six community colleges, 30 percent earned their associate degrees within two years, and nearly 60 percent did so within three years. (By comparison, just 12 percent of students who weren't in the program got their associate degrees within two years, whereas 24 percent did within three years.)

Zane State College in Ohio added advanced courses along with a special counseling program for new students after discovering it was losing not only its lowest-performing students but also its highest-performing ones. It saw as much as a 24 percent increase in the number who finished their first year.

College of the Ouachitas in Arkansas changed its culture from recruiting students to fill seats to making sure they earned their associate degrees once there. The proportion of students there who graduate within three years has increased from 9 percent in 2001 to 25 percent this year.

(This story was produced by The Hechinger Report, a nonprofit, nonpartisan education-news outlet based at Teachers College, Columbia University.)

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