One important principle of social psychology, writes Nisbett, is that some big-seeming interventions have little or no effect. This article discusses a number of cases from the field of education that confirm this principle. For example, Head Start seems like a big intervention, but research has indicated that its effects on academic achievement gaps are slight because it is not always implemented well. Fortunately, research has also found that some even bigger preschool interventions, such as the Perry Preschool Project and the Abecedarian Project, do produce large effects. On the school level, Nisbett asserts that charter schools in general do not necessarily produce positive effects, but that certain intensive types of charter schools--for example, KIPP schools--do. Nisbett also discusses a second principle of social psychology--that small interventions sometimes produce large effects. He gives several examples, such as Carol Dweck's work, which teaches students that they can increase their intelligence through their own efforts. The author concludes that to close achievement gaps, we need to be far-sighted enough to invest in very big interventions that are effective--and creative enough to consider small interventions as well.