Introduction:
The drugs consumption at early age is an important risk factor for its later use and progression to more serious forms. The objective of the study is to analyze the effectiveness of the program "Be yourself" (STM), to reduce the consumption of tobacco in adolescents. The sample consists of 893 participants (48.4% men, 51.6% women), mean age = 12.74 years, from three public secondary schools in Teruel.

Methods:
Model: Non-randomized controlled quasi-experimental study (30.5% GC, 69.5% GE), longitudinal with three times: pre, post at the end of the intervention, and follow-up at six months. Variables: "Sex"; "Frequency of tobacco use last 30 days"; "Experimental condition". Instruments: Questionnaire Frequency of drug use developed ad hoc based on the 2012 STUDIES Survey (PNSD, 2014). Statistical analysis: Central tendency indices, contrast of the difference of means between GC and GE through the Levene test and the Cohen d for the effect size.

Results:
The "STM" program achieve to moderate in GE the frequency of tobacco use in the last 30 days interval, being effective at the end of the application of the intervention (31% less than GC). Considering the gender perspective, the "STM" program achieve to moderate in GE the use of tobacco in the interval of the last 30 days in women (40% less than CG) and decrease it in men (22% less than GC), being effective at the end of the application of the intervention.

Conclusions:
The "STM" program is effective in reducing the frequency of tobacco use, both in men and women, although more in women. In agreement with other studies, it is observed that their effects decrease or disappear in the follow-up. Reinforcement sessions are recommended.