Its founders are dead; its disciples are scattered; its millions were all spent long ago. But tens of thousands of Americans in their late thirties still carry the message of New Math in their heads, if not in their hearts. Jeffrey W. Miller was one of that baffled legion bushwhacked with a catechism of sets and frames and complementation. He looks back over the brief, busy history of an educational revolution to find why it all seemed so plausible at the outset; and he discovers in the debacle lessons that we would do well to remember as America embarks on yet another cycle of educational reform.