The number of college students taking courses online is surging, creating a tough dilemma for educators who want to prevent cheating.

Do you trust students to take an exam on their own computer from home or work, even though it may be easy to sneak a peek at the textbook? Or do you force them to trek to a proctored test center, detracting from the convenience that drew them to online classes in the first place?

The dilemma is one reason many online programs do little testing at all. But some new technology that places a camera inside students' homes may be the way of the future - as long as students don't find it too creepy.

This fall, Troy University in Alabama will begin rolling out the new camera technology for many of its approximately 11,000 online students, about a third of whom are at U.S. military installations around the world.

The device, made by Cambridge, Mass.-based Software Secure, is similar in many respects to other test-taking software. It locks down a computer while the test is being taken, preventing students from searching files or the Internet. The latest version also includes fingerprint authentication, to help ensure the person taking the test isn't a ringer.

But the new development is a small Web cam and microphone that is set up where a student takes the exam. The camera points into a reflective ball, which allows it to capture a full 360-degree image. (The first prototype was made with a Christmas ornament.)

When the exam begins, the device records audio and video. Software detects significant noises and motions and flags them in the recording. An instructor can go back and watch only the portions flagged by the software to see if anything untoward is going on - a student making a phone call, leaving the room - and if there is a sudden surge in performance afterward.

The inventors admit it's far from a perfect defense against a determined cheater. But a human test proctor isn't necessarily better. And the camera at least ``ensures that those people that are taking classes at a distance are on a level playing field,'' said Douglas Winneg, Software Secure's president and CEO.