This report reviews the research on summer school and demonstrates that summer school makes a difference in students' lives if it is done right. A survey of more than 1,000 schools in the southern United States found that one-third of the responding schools did not offer summer school, many programs being the victims of budget cuts. Of those schools that ran summer programs, few used carefully planned, high-quality instruction. In states with strict promotion requirements, summer school is the last hope for failing students to avoid repeating a grade. Even if strict promotion standards are not a factor, the lowest performing students need summer school to keep from falling further behind. The report claims that if states are serious about ending social promotion and reducing retention rates, they should make summer school an integral part of a year-round program, ensuring that it is available to all failing students at no cost to parents. Such programs should meet clear standards for quality, length, and scheduling of classes and should respond to individual needs through the use of innovative and creative teaching strategies. Furthermore, summer school should place a priority on student mastery of reading and math skills, skills that are taught by teachers who have special training and/or proved ability to help struggling students. (RJM)