...the Joan Ganz Cooney Center's research on digital reading comprehension and retention in children, which found that "reading comprehension and reader engagement for children between print books and e-books was similar. However, between print books and enhanced e-books, it was a different story.<idle musing>
"While children engaged more actively with enhanced e-books versus print books, their reading comprehension went down. The study found that when enhanced e-books featured interactivity that wasn't directly tied to the narrative or the text, it distracted both the children and parents from the story and thereby affected comprehension and retention."
Maybe that is the reason repeated surveys of college students say they prefer their textbooks as books—less distractions. I have to admit, when I'm reading an e-book on the computer, I get distracted by the options...