Journal of

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The present research aimed to investigate the effectiveness of short-term and long-term life skills training in decreasing the aggression among the adolescents. The sample comprised 400 male and female students studying in the high schools of Karaj, who responded to two questionnaires of Life Skills and Aggression Questionnaire and based on their mean score were randomly assigned to the experimental and control groups (100 male and 100 female). Subsequent to ten life skills training sessions for the experimental group, both groups were reassessed by both of the questionnaires. Covariance analysis indicated that increase of life skills decreased the level of aggression among the individuals. In order to test out the stability of the training effects, two 30-individual groups with low and high scores were selected and were tested in terms of the research variables. Results demonstrated that in the first six month, the mean of groups decreased. However, this was desirable according to the psychological statistics. It's worth mentioning that, the weak group demonstrated a greater decrease. Furthermore, in the second six month, the weak group attended five training sessions which increased their level of life skills and decreased the level of aggression to a more considerable level as compared to the strong group which resulted in lower mean by the end of the training. It can be concluded that the repetition of the training with time interval increases the level of awareness and mastery of life skills and we can evidence higher decrease of aggression and more stability of the results

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