Janet Killen spent $5,500 and four years of effort earning what she thought was a master's degree from Canyon College, an online school originally based in Idaho.

But when she presented her nursing degree in 2007 to Lane Community College in Eugene, Ore., where she teaches nursing, she was devastated to learn it had no value.

Furthermore, she was told, she could face civil and criminal charges for passing the degree off as legitimate.

"I felt really violated," Killen said. "I worked very hard for this degree."

Killen isn't alone. According to the state of Oregon's Office of Degree Authorization, a consumer watchdog agency that protects state residents against unauthorized degrees, some 4,000 other students have been cyber-scammed by Canyon College alone, and thousands more have been victimized by other schools.

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Harvey Lyter, proprietary schools coordinator for the Idaho State Board of Education, said that under Idaho law, Canyon College doesn't have the authority to be granting degrees.

"The issue with Canyon College is that they're not accredited by an agency recognized by the U.S. Department of Education, or the Council for Higher Education Accreditation, or the Idaho State Board of Education," he said.

"Canyon College claims that it's accredited by some outfit that nobody's heard of, takes people's money and then supplies them with a transcript and diploma that's not worth the paper it's written on."

But Canyon College says that different states accept different degrees, and that Canyon works to help students if they feel they've been wronged.

"Every state varies in terms of what degrees they accept, and we always tell our students to check their state's requirements," said Phil Braun, director of Administrative Services at Canyon College. "When someone isn't satisfied, we have to handle it, and we gave Janet back the money within one business day."

Braun says that seeking accreditation may actually harm the educational experience for Canyon students.

"Accreditation in the U.S. is not required, and to become accredited by federal agencies, you have to pay expensive fees, charge your students more and accept federal-backed student loans," he said. "We are an independent college with affordable tuition, and we want to maintain that."

Killen, 59, is upset and frustrated — but still feels she received a good education.

She says her online classes seemed comparable to curricula at other schools, but faults the school for not informing her they were not accredited.

"I earned every bit of it and I've been able to use what I learned. They should have told me it wouldn't be recognized," said Killen.

Canyon is not the only Web-based school with problems; many schools claim to be accredited but hand out worthless diplomas to their graduates.

The problem: The organizations these online schools say have accredited them are often bogus themselves.

Of the thousands of online schools with glitzy advertising about their degrees stamped across their Web pages — ranging from traditional universities that offer online and in-person blended programs, to universities that operate solely on the Web — it's difficult for a student to find one with value and credibility.

"To avoid these diploma mills, know that a school should be either regionally and/or nationally accredited by an agency that is recognized by the U.S. Secretary of Education as a reliable authority," said Lyter.

"Proper state registration and academic accreditation are the two most critical issues for any potential student to be aware of. These accrediting agencies can be found on the U.S. Department of Education's Web site."

Karen Solomon, associate director of accreditation at the North Central Association of Colleges and Schools, a reputable accrediting agency, said that nationally accredited schools tend to have more specialized, practical-oriented programs than regionally accredited ones.

"The only difference is that nationally accredited schools may or may not have the rigor of general education expectation, because they're based more on a specific career field or vocation," said Solomon.

Moreover, regionally and nationally accredited schools allow students to easily transfer their course credits to other legitimately accredited universities and to be eligible for federal student aid — something a bogus school won't likely offer.

Kristen Morris, 23, who lives in Newport News, Va., was offered extensive financial resources when she registered for courses at Jones International University, an online university based in Centennial, Colo.

"As soon as I got accepted, I got a call from a counselor who walked me through the entire financial aid process and any scholarship opportunities available," said Morris. "This made me feel a lot more confident about enrolling in classes."

In contrast, Killen said a counselor explained to her that no financial support was available for Canyon College.

"They told me that, since they'd maintained such low costs, they couldn't offer financial aid," she said. "Now I know the truth."

Another element to be wary of when seeking an online education is faculty qualification.

Since the teaching style of an online course differs greatly from a course taught in the classroom, student success is heavily based on the instructor's approach, and each online school's faculty training methods should reflect that.

Bill Husson, the vice president of Strategic Alliances at Regis University, an accredited online and classroom-based hybrid university in Denver, said that every faculty member who wishes to teach an online course must "undergo a week-long training program on how to navigate the course management systems and facilitate online communication."

After completing this program, each faculty member's performance is monitored throughout their first online class. They also must also attend regular workshops and seminars.

"We provide this because faculty tends to find it very difficult to teach their first few online classes," said Husson. "They have to re-learn all of the teaching customs and mechanisms and adapt them to the online environment, which can be difficult to do."

According to Solomon, the mark of a reputable online university is its level of personalized service and round-the-clock technical support throughout the duration of the course.

"During the accrediting process, we're looking at how courses are developed, if the curriculum fits the program that's being offered and has learning outcomes, and if there is support for students at nights and on weekends," she said.

"To become accredited, an institution must prove it's developed a true commitment to online learning."

As for Killen, the Oregon Office of Degree Authorization worked on her behalf to get Canyon College to refund her money. But she was one of the lucky ones.

"This is a success story for one person, but she still can't get the time or effort back that it took to complete four years of coursework," said Lyter.

"There are many fine and reputable online schools out there," he said. "Unfortunately, as is always the case with the Internet, the first standard of practice is 'let the buyer beware,' so always cross-check what the school tells you with your state officials."

"Never assume a catchy, professional-looking Web site is any guarantee of the quality of their product," warned Lyter.