As the amount of resources allocated to out-of-school (OST) programming and policymakers' demands for research-based results increase, there is increasing interest in rigorous research designs to examine OST program outcomes. This issue of "Out-of-School Time Evaluation Snapshots" reviews 27 quasi-experimental and experimental OST evaluations and provides an overview of the impact of OST programs on an array of academic, prevention, and youth development outcomes. The evaluations reviewed represent a range of programs from small single-sites to city- and statewide programs operating multiple sites in multiple locations, to national programs such as the 21st Century Community Learning Centers. Findings from 25 evaluations assessing academic outcomes suggest that OST participation is linked to better attitudes toward school, higher educational aspirations, better school performance, higher school attendance, and less disciplinary action. The 12 evaluations assessing prevention outcomes found links to avoidance of drug/alcohol use, decreased delinquency/violent behavior, increased knowledge of safe sex, avoidance of sexual activity/pregnancy, and increased skills for coping with peer pressure. The 15 evaluations assessing positive youth development outcomes found links to decreased behavior problems, improved social and communication skills, increased community involvement and broadened world view, and increased self-confidence and self-esteem. The report concludes by noting that OST programs vary greatly in program quality and participation consistency, and that programs need to collect implementation data for program improvement as well as collect data to satisfy stakeholder accountability requirements. Appended is a brief description of all programs reviewed, a list of 32 evaluation report references, and a table of outcomes linked to OST program participation. (Contains an 11-item bibliography of other OST evaluation reviews.) (KB)