After six years in the famous Milwaukee Project, experimental subjects’ IQs were 32 points higher than controls’. By age fourteen, this advantage had declined to 10 points.83 In the Perry Preschool program, experimental subjects gained 13 points of IQ, but all this vanished by age 8.84 Head Start raises preschoolers’ IQs by a few points, but gains disappear by the end of kindergarten.
