Cobb County is one of a growing number of Georgia school districts placing students who failed classes on their first attempt in online classes, giving them a chance to make up the course credit.

But statewide, most students pass the online classes without mastering the material.

Educators say online credit recovery courses can keep students from dropping out. They can work through the online lessons at their own pace and on their own schedule. And some students say they prefer online courses to traditional classrooms.

Some teachers and students say the largely unregulated courses do more to boost graduation rates than help students learn material they didn’t get the first time around, leaving them with high school diplomas but without the skills they need to succeed in college or at work.

Statewide, about 90 percent of Georgia students who took one of these courses last year in subjects covered by state tests passed the course itself. But an Atlanta Journal-Constitution analysis of results of the state-required tests found only about 10 percent of them were proficient in the subject.

In Cobb County, about 74 percent of students in those classes passed the course, but just 15 percent were proficient on the subject, according to state data. Cobb officials say their data show similar rates.

Cobb officials say a student’s performance in class may not match up exactly with his or her performance on a state test. And they note some students whose state test performance doesn’t indicate they’re proficient may still have learned some course content.

“The assessment is just a single dot point in a semester-long or year-long course,” said Ehsan Kattoula, Cobb senior executive director of accountability and research.

>>Read more: Retaking classes online: ‘Awful if someone really wants to learn’