Background and aims: Gambling in adolescents is a public health concern. This study sought to examine patterns of gambling among Connecticut high-school students using seven representative samples covering a 12-year period. Methods: Data were analyzed from N 5 14,401 participants in cross-sectional surveys conducted every two years based on random sampling from schools in the state of Connecticut. Anonymous self-completed questionnaires included socio-demographic data, current substance use, social support, and traumatic experiences at school. Chi-square tests were used to compare socio-demographic characteristics between gambling and non-gambling groups. Logistic regressions were used to assess changes in the prevalence of gambling over time and effects of potential risk factors on the prevalence, adjusted for age, sex, and race. Results: Overall, the prevalence of gambling largely decreased from 2007 to 2019, although the pattern was not linear. After steadily declining from 2007 to 2017, 2019 was associated with increased rates of gambling participation. Consistent statistical predictors of gambling were male gender, older age, alcohol and marijuana use, higher levels of traumatic experiences at school, depression, and low levels of social support. Discussion and conclusion: Among adolescents, older males may be particularly vulnerable to gambling that relates importantly to substance use, trauma, affective concerns, and poor support. Although gambling participation appears to have declined, the recent increase in 2019 that coincides with increased sports gambling advertisements, media coverage and availability warrants further study. Our findings suggest the importance of developing school-based social support programs that may help reduce adolescent gambling.  Kulcsszavak: gambling, adolescents, substance use, risk behaviors