Two themes we have been following, cheating scandals and the rise of online courses, have now combined for a new dilemma facing American colleges and universities.

Wall Street Journal reporter Douglas Belkin takes an in-depth look at how institutions of higher learning are struggling to address problems associated with student cheating.

Traditional colleges and a new breed of online-education providers, trying to figure out how to profit from the rising popularity of massive open online courses, are pouring resources into efforts to solve a problem that has bedeviled teachers for centuries: How can students be stopped from cheating?

Coursera, a Silicon Valley-based MOOC, recently launched a keystroke system to recognize individual students’ typing patterns. EdX, its East Coast rival, is employing palm-vein scans. Other strategies include honor codes, remote web-camera proctors and test-taking centers.

Until recently, MOOCs have offered only certificates of completion that in some cases come with a letter grade. Typically, papers have been assessed by fellow students and tests marked by computers. Students frequently study together in online chat rooms—and there is often little to prevent them from cheating on tests or papers.

The efforts to stamp out cheating underscore just how much the stakes are rising. Until now, MOOCs have generally been free of charge and the most popular classes have attracted 150,000 students at a time. More than three million students from at least 160 countries have signed up for courses ranging from “A Beginners Guide to Irrational Behavior” to “Financial Engineering and Risk Management.” Given the vast profit potential, MOOCs are scrambling to ensure the academic integrity of the courses.

“The concern [about online cheating] has been around for a while, but MOOCs’ scale is so large it really magnifies the issue,” said Cathy Sandeen, a vice president at the American Council on Education, which last week recommended that five Coursera classes should be eligible for academic credit, in part because they have standards in place to prevent cheating.

Coursera’s keystroke system relies on an algorithm developed in-house that analyzes typing patterns. Among the metrics it takes into account: error patterns, typing speed and even how long specific keys are held down.

Belkin also describes another cheat-prevention approach:

Both Udacity, another MOOC provider, and Coursera have teamed up with an online test-taking company called Proctor U that pays employees in Alabama and California to monitor test takers through a webcam trained on the student’s face.

Before every test begins, the proctor asks the test taker to pan the room with their web camera, said Jarrod Morgan, a vice president at Proctor U. During that sweep, proctors see all sorts of things: answers on Post-it Notes taped to the computer screen, another person sitting in the room, a second laptop open to Google.