One class, for instance, had more than 100,000 enrolled, says Karl Ulrich, vice dean of innovation at Wharton.
The school's new series offers some of what students learn during their first semester of the full-time, in-person program, he says.
The introductory classes cover corporate finance, financial accounting, marketing and operations management. "They're in general about 40 percent of what you might get in an introductory course on campus," he says. "They're the language of business, basically."
Experts say MOOCs can be a great way to learn business skills without getting an MBA.
"That's a good option for someone trying to gain a broad overview of a particular topic," says Advani.
Students don't typically earn grades in MOOCs or pay fees. Anyone around the world with Internet access can sign up.
"The nice thing about the MOOCs is they're very easy to try," says Ulrich. "I would recommend that people just sign up."
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