This study sought to examine high school students’ self-reported drinking behaviors following the introduction of flavored malt beverages, also known as alcopops, to the US market. We hypothesized that adolescents’ reported drinking behaviors would be significantly altered following the introduction of alcopops in the US. A cross-sectional time series Youth Risk Behavior Survey data set was created from publicly available data collected by the Centers for Disease Control and Prevention (N = 60,426) and used to conduct secondary data analysis, using an interrupted time series quasi-experimental design. Segmented regression analyses estimated how much the introduction of alcopops in the US affected drinking behaviors, whether the effects were immediate and/or delayed, and whether there may have been other factors than the intervention that could explain the effects. Respondents aged ≥18 years had statistically significant increases in three drinking behaviors after alcopops were introduced. Binge drinking increased significantly in the entire study population between 1997 and 2001, remaining steady in 2001–2003. Drinking on school property increased in some groups between 2001 and 2003. The statistically significant increases identified for some drinking behaviors and, for most behaviors, in certain population subgroups can be used to develop prevention strategies that are targeted accordingly.