Tuition was due. The rent was, too. So Mary Mbugua, a university student in Nyeri, Kenya, went out in search of a job. At first, she tried selling insurance policies, but that only paid on commission and she never sold one. Then she sat behind the reception desk at a hotel, but it ran into financial trouble.

Finally, a friend offered to help her break into “academic writing,” a lucrative industry in Kenya that involves doing school assignments online for college students in the United States, Britain and Australia. Mbugua felt conflicted.

“This is cheating,” she said. “But do you have a choice? We have to make money. We have to make a living.”

Cheating in college is nothing new, but the internet now makes it possible on a global, industrial scale. Sleek websites — with names like Ace-MyHomework and EssayShark — have sprung up that allow people in developing countries to bid on and complete American homework assignments.

Although such businesses have existed for more than a decade, experts say demand has grown in recent years as the sites have become more sophisticated, with customer service hotlines and money-back guarantees. The result? Millions of essays ordered annually in a vast, worldwide industry that provides enough income for some writers to make it a full-time job.

The essay-for-hire industry has expanded significantly in developing countries with many English speakers, fast internet connections and more college graduates than jobs, especially Kenya, India and Ukraine. A Facebook group for academic writers in Kenya has over 50,000 members.

After a month of training, Mbugua began producing essays about everything from whether humans should colonize space (“it is not worth the struggle,” she wrote) to euthanasia (it amounts to taking “the place of God,” she wrote). During her best month, she earned $320, more money than she had ever made in her life. The New York Times is identifying Mbugua by only part of her name because she feared that the attention would prevent her from getting future work.

It is not clear how widely sites for paid-to-order essays, known as “contract cheating” in higher education circles, are used. A 2005 study of students in North America found that 7% of undergraduates admitted to turning in papers written by someone else, while 3% admitted to obtaining essays from essay mills. Cath Ellis, a leading researcher on the topic, said millions of essays are ordered online every year worldwide.

“It’s a huge problem,” said Tricia Bertram Gallant, director of the academic integrity office at the University of California, San Diego. “If we don’t do anything about it, we will turn every accredited university into a diploma mill.”

When such websites first emerged over a decade ago, they featured veiled references to tutoring and editing services, said Bertram Gallant, who also is a board member of the International Center for Academic Integrity, which has worked to highlight the danger of contract cheating. Now the sites are blatant.

“No matter what kind of academic paper you need, it is simple and secure to hire an essay writer for a price you can afford,” promises EssayShark.com. “Save more time for yourself.”

In an e-mail, EssayShark’s public relations department said the company did not consider its services to be cheating, and that it warned students the essays are for “research and reference purposes only” and are not to be passed off as a student’s own work.

“We do not condone, encourage or knowingly take part in plagiarism or any other acts of academic fraud,” it said.