The education business has a short memory, Steve Sailer notes, which keeps it from getting discouraged but also prevents it from learning from its mistakes:
One reason fads are so common in public schools is that the incentive structure pays more to administrators with Ph.D.’s. A doctorate in education means you came up with some gimmick and then spent a few years documenting it. Education schools are thus novelty generation machines. Nobody gets to call himself “Doctor” for being good at making old ideas work together.
Outside of Ed schools, however, novelty isn’t enough.