Research shows that summer slide--the loss of learning over the summer break--is a huge contributor to the achievement gap between low-income students and their higher-income peers. In fact, some researchers have concluded that two-thirds of the 9th-grade reading achievement gap can be explained by unequal access to summer learning opportunities during elementary school. The author of this article, chief executive officer of a summer program called Horizons National, describes how schools can take advantage of community and foundation partnerships to give their low-income students "the sort of enrichment typically reserved for more-affluent youngsters." During the 6-week Horizons summer program, students realize average gains of three months in reading and math skills. Horizons and similar programs, Smith writes, have produced positive results in terms of student motivation and attitude.