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Inexpensive training isn't the only lure. Brightpearl, an online business software management developer, started to use Udemy last fall to help train a new team of salespeople. It found that the new team produced 32 percent more in revenue compared with a previous group of new hires, who had been taught in a traditional instructor-led class.
"It's easy to go back to the application and review and improve your skills," said Carter Perez, senior vice president of sales at Brightpearl. "I think that's led them to be able to get out of the gate faster."
Online courses are not necessarily cheap to produce. Perez declined to disclose how much Brightpearl spent to launch its online university but said that the company invested about 500 hours to produce the online video tutorials, which it is also using to offer certification for its business partners. The MOOC nonprofit founded by Harvard University and MIT has said it can cost hundreds of thousands of dollars to develop one university course online.
Businesses spend $1,195 on average per employee for training each year, according to a report by the American Society for Training & Development. The ambition of the online educators is to prove to businesses that they can save hundreds, if not thousands of dollars, in productivity, as well as the cost of hiring an instructor, sending employees to a conference or beefing up their IT desk to manage, say, an operating system migration for the entire company.
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1-800-Flowers has partnered with Udemy to create a Web version of its BloomNet Floriology Institute, where members of its retail florist network can take classes on the latest trends in floral design. Now its florists don't necessarily have to travel to its headquarters in Jacksonville, Fla., or to a regional seminar for training.
"They're a little bit of everything in their store, so they need a system that is flexible so they can take it when they can take it," said Lisa Carmichael, vice president of marketing and new business development for BloomNet, a subsidiary of 1-800-Flowers.
The benefits of learning hands-on with an instructor can't be erased: On average, just 4 percent of students managed to finish an online class, according to the University of Pennsylvania study. But for businesses, online learning is not so much about sitting through an entire lecture and earning an A, but being able to take new information and apply it to jobs immediately.
"We believe that if you know it, it doesn't matter if you sit through it," said Dennis Yang, Udemy's president and chief operating officer.
Compared with an in-person class or seminar, online courses also offer much more flexibility for employees, who have varying levels of skill and need varying amounts of coaching. "Not everyone needs the same instruction," said Lynda Weinman, co-founder of Lynda.com, another California-based online learning company.
Lynda.com's business began well before the MOOC revolution: The site started 18 years ago with a library of online video tutorials mainly focused on photography, graphics and design. Since then, it has expanded to more than 15,000 hours of curriculum, including 450 business-related courses, and corporate customers have become the fastest-growing segment of Lynda.com's revenues, Weinman said. Bank of America, Disney and Apple are among the companies that pay a fee to give their employees unlimited access to the site.
"It is a new era of abundant learning, where there are so many avenues for people to increase their skills," Weinman said. "It's giving people a lot of options." Their employers, too.
—By Ellen Lee, Special to CNBC.com