Textbook publishers revamp e-books to fight used market

A booming market in recent years for selling and renting used college textbooks has saved students across the United States a ton of cash. But it has put textbook publishers in a bind. They don't make a cent unless students buy their books new. So increasingly, publishers like Pearson and McGraw-Hill Education are turning to a new model: Creating online versions of their texts, often loaded with interactive features, and selling students access codes that expire at semester's end. Publishers save on printing, shipping and process returns. The e-books are good for learning and good for their bottom line. There's just one catch: Persuading students to go digital isn't easy.