The spiral of destruction.

We're not talking about instability in the Middle East or Ebola.

We're talking textbooks.

Yesterday on All Things Considered, our friends at Planet Money explored the rise in college textbook costs . One big reason for the increase: the Internet. It gave students a vibrant marketplace where they could buy and sell used textbooks. As a result, publishers sold fewer new books and steadily raised prices. As NPR's David Kestenbaum put it:

"This produced what one textbook salesman called a 'spiral of destruction.' Students found new ways to avoid the higher prices. Textbook rentals. Illegal downloads. Some skipped buying the textbook. Which meant the textbook companies were selling even fewer books. So they raised the price for new books again."

Kestenbaum ended his story this way:

"Students, it seems, have fought the publishers to a draw. One textbook executive told me, the way out of all this is to replace textbooks with something better: software. Basically digital, interactive versions of textbooks. They're cheaper. Easy to update. For students, there is one drawback. You can't sell them back to the bookstore — or to anyone — at the end of the semester. There is no used market for digital textbooks."

A great story. But its ending is really just the beginning when it comes to talk of e-textbooks.

The Textbook Goes Digital

A bunch of companies, including startup Packback , as well as Chegg , Campusbooks , Bigwords and DealOz , are, in the parlance of our times, disrupting the textbook market. They're a kind of Kayak for textbooks, trying to make it easy and fast to compare used-book prices. Some are even getting into the textbook rental business. That is, the e-textbook rental business.

Exhibit A: Packback. It allows students to rent digital books by the day. "A student can also convert money spent on daily rentals toward a semester or yearlong rental," says Mike Shannon, the CEO of Packback. He recently co-founded the company with fellow Illinois State University classmates.

This shift toward digital texts has been surprisingly slow, Shannon says, for a generation of digital natives. One study says just 3 percent of college students recently used a digital textbook as their primary course material. The reason: It's still cheap and easy to buy a used book. That said, Shannon is betting that students who use the Internet to buy or sell a used book won't consider e-textbooks a stretch. "It's an affordable alternative to the used book, which incentivizes students to try out digital formats, which is ultimately where the industry needs to go," he says.

Packback faces plenty of challenges ... and challengers, including CourseSmart , which claims to offer the largest selection of e-textbooks and digital course materials, and the book industry's 800-pound gorilla, Amazon.com .

Today, textbook purchases still top rentals. But, according to the on-campus retail trade group the National Association of College Stores , rentals are rapidly gaining ground. And that could open the door for e-textbooks.

It helps that the pro-rental camp has a valuable ally. The nation's higher-ed libraries have taken a lead role in opposing the textbook status quo, largely because increasing costs are pricing low-income students out of the market.

"We are advocates for affordable education resources," says Karen Williams, president of the Association of College and Research Libraries. "We're not saying all publishers are bad, but they do have a lock on the market in an odd way."

Many college and university libraries have responded by creating their own education resources and textbooks that students can access free.

One example: a collaborative project spearheaded by the University of Minnesota , where faculty partnered with the library to offer open materials to other institutions to "help instructors find affordable, quality textbook solutions."

The University of California, Los Angeles is also getting into the act with an innovative pilot project called Affordable Course Materials Initiative . It's meant to encourage professors to rework their syllabuses to include more low-cost or free course materials.

In many cases, libraries are partnering with their campus bookstores to offer affordable, group licensing for some textbooks — so all students can have access and at a much lower cost. That, of course, cuts into stores' bottom lines. But, Williams says, "most of them understand it's in the best long-term interest of the institution to lower costs for students. They know they will have to increase their revenue from other sources."

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