"All of the Orland studio’s volunteers — there are 120 of them, and more eager readers are on a waiting list — have to audition, and those who make the cut undergo three months of training. And it’s not just reading the words, it’s also trying to describe to the listener any charts, maps or graphics contained in textbooks. Learning Ally tries to match readers with their particular background or expertise. A couple of former math teachers, for instance, are tag-teaming on a geometry book."