Then, too, just as the old mechanical production line pressed physical materials into preset and unvarying molds, so mass education tended to treat students as objects to be shaped, manipulated. “Instruction” generally meant pressing information onto passive students. Lectures, the most common mode of instruction in mass education, called for very little student involvement. This mode, one of the least effective ever devised by man, served well enough in an age that demanded only a specified fragment of each human being’s whole abilities. There was, however, no warranty on the human products of mass education.