Adaptive learning is an increasingly popular catchphrase denoting educational software that customizes its presentation of material from moment to moment based on the user’s input. It’s being hailed as a “revolution” by both venture capitalists and big, established education companies. Starting this fall, Knewton’s technology will be available to the vast majority of the nation’s colleges and universities and K-12 school districts through new partnerships with three major textbook publishers: Pearson, MacMillan, and Houghton Mifflin Harcourt. And Ferreira’s done all this even though he says neither his investors nor his competition, to say nothing of the public or the press, really understand what Knewton can do.