Before the financial crisis of 2008, the typical answer to differentiating yourself in a job market crowded with bachelor’s degrees was to get yet more college by earning a master’s degree.

But since the recession, enrollment in graduate school has been essentially flat as fewer students seem to want to take on the debt of going back to school or question the return on investment in a tough job market. A front-page article in the Wall Street Journal earlier this month noted that graduate students hold 40 percent of the $1.19 trillion in outstanding student loans, although they represent just 14 percent of students in higher education.

But it’s not just the hefty price tag that is turning students off from graduate school.

A more fundamental transformation is underway in how recent college graduates supplement their education as they start their careers. Rather than plug into the formal learning structure of traditional higher education, young adults are increasingly navigating what George Siemens describes as a “shadow learning economy” that mirrors the behavior of twenty-somethings in today’s Uber economy where they favor alternative start-ups over legacy enterprises.

This new learning economy is made up of a plethora of providers that offer education in short spurts, online or in face-to-face classes. The programs are just a faction of the cost of graduate school, or in some cases, free, and focus on specific skills that students need to get a job. The organizations in this space are hardly household names but they are already attracting millions of students, many of them recent college graduates. There are three types of players in this new arena:

Boot camps. There are some 63 computer coding boot camps operating in the U.S. and Canada that teach basic programming skills in 10-week sprints to students who typically don’t have previous experience. It remains unclear whether the boot-camp model can easily translate to other career fields, where there isn’t as much demand for workers who are willing to foot the typical $11,000 bill for these programs. For now, students can’t use federal financial aid dollars at the boot camps, although the U.S. Education Department is considering an experiment to allow them to partner with existing colleges where the funds could be used for courses.

Massive Open Online Courses (MOOCs). MOOCs have attracted their fair share of criticism in recent years because only about one in ten students end up completing an entire course. But applying the traditional measures of how we define success in higher education to this new way of learning misses the intent of many of the students who have taken the classes. Some people enroll to try out a course or they want to watch a particular lecture for its content. They never planned to complete the course, and they have nothing to lose when they stop taking it because it was free.

Digital learning resources. The Web is full of DIY education sites, from YouTube to iTunesU, where students can piece together their own curriculum. Some of these sites have more visitors in one month than universities have students over an entire century. The Khan Academy, for instance, serves some 10 million people a month with 5,000 videos. reaches more than 4 million people a year with its how-to tutorials online in everything from management skills to programming. To give you a sense of the size of this market, LinkedIn bought for $1.5 billion in April.

Taken together, these organizations compose a new ecosystem of education that represents a seismic shift in how students—really any of us—will access learning in the future.

Welcome to the era of “just-in-time education”; training when, where, and how we want it. No need to invest several years of your life or tens of thousands of your dollars in a certificate or degree program—just learn a skill when work or life calls for it. And if the Education Department recognizes these providers as part of the federal financial aid system, the market is only likely to grow.

It’s always been assumed that the disruption of traditional higher education would begin at the undergraduate level. But if disruption is going to happen, the trends of this new learning economy point to it starting with graduate and professional education.