Background. The rapid expansion of legalized gambling in the United States necessitates evaluation of its impact on vulnerable populations, especially adolescents. Methods. Gambling behavior in 135 adolescents in residential placement in northwestern Louisiana was measured using the South Oaks Gambling Screen-Revised for Adolescents. Results, During the past year, 41% of these adolescents reported minimal problems with gambling, 21% reported level 2 or problem gambling, and 38% reported level 3 or pathologic gambling. In this population, the first drink of alcohol, the first cigarette, and the first experience with gambling began on average at 11 years of age, with the first use of marijuana and the first episode of alcohol intoxication occurring a year later. Conclusion. The level 2 rate of gambling exceeded the upper extreme of the adolescent community sample range, and the level 3 rate was approximately six times the reported level 3 community prevalence rate for adolescents. Residential placements sites should be considered when developing prevention programs for gambling disorders.