Competency-based education is in vogue — even though most people have never heard of it, and those who have can't always agree on what it is.

A report out todayfrom the American Enterprise Institute says a growing number of colleges and universities are offering, or soon will offer, credits in exchange for direct demonstrations of learning. That's a big shift from credit hours — the currency of higher education for more than a century — which require students to spend an allotted amount of time with instructors.

A "competency" might be a score on a standardized exam or a portfolio of work. These are types of credit familiar to most people: think AP exams. But they are being applied to core requirements, not just used for skipping electives or introductory courses.

And in a newer, even more experimental trend, institutions such as Western Governors University are offering entire degree programs that allow students to move at their own pace, completing assignments and assessments as they master the material.

The major argument in favor of competency-based programs is that they will offer nontraditional students a more direct, more affordable path to a degree. This argument is especially made on behalf of older students who can earn college credits based on prior workplace or life experience. The AEI report, by Robert Kelchen, found that 9 out of 10 competency-based students are older than 25.

The business and instructional models of competency-based degree programs are diverse.

Some, like StraighterLine and Capella University, are for-profits; others, like Southern New Hampshire University's College for America program, are nonprofits. Still others, like University of Maryland University College or Rio Salado College, are part of public university or community college systems.

And the numbers are large. Most programs don't report their competency-based enrollment, but there are nine colleges that are entirely competency-based; these nine colleges alone enroll more than 140,000 undergraduates and 57,000 graduate students.

From a racial, ethnic and gender standpoint, these colleges resemble college enrollments as a whole. This, conversely, makes them less "nontraditional" than some other mainly online programs.

Whether competency-based programs will really save students money is a bigger question.

Exams, like CLEP, UExcel or ACE, cost less than $100 for three college credits. And online programs like Western Governors University have "all-you-can-eat" pricing models, where students pay a fixed rate every six months for all the credits they can earn.

These usually represent savings over other online programs — but time is money. A student who is studying only part-time and progressing more slowly than the average may end up paying more, not less, than in a traditional program. And some of these newer offerings aren't eligible for federal student aid, which drives students who can't pay into the expensive private loan market.

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