Adolescents, worldwide, are starting their sexual life earlier and earlier, which expose large scale to sexually transmitted diseases (STDs) or an unwanted pregnancy. The orientation toward sexuality must also include the school, given that, in many cases, students do not have access to the theme in family life. This work was performed during the development of the discipline in the School of Health and Community of Parasitology and Pathology of ICBS sector - UFAL, which provided planning and intervention of a health education project to be implemented in public schools. The choice of school was not a random event, since were running in parallel activities Supervised Required, the Pedagogical Practices sector of ICBS - UFAL for the degree course in Biological Sciences. The approach was qualitative and quantitative. The study was conducted with 135 adolescents, aged between 10 and 18, students from 4 different classes, covering all grades of primary school 2. The classes of sixth and seventh years belonged to the State School Prof. Jose Maria Correia das Neves, located in the Prado neighborhood, and groups of eight and nine years were in the State School Prof. Sebastiao da Hora, situated in the neighborhood Pitanguinha, both in Maceio. And the second" major STDs and contraception", the first themed" Adolescence and Sexuality": two lectures were given on different days. Before and after the lectures, activities such as games, workshops and a questionnaire on the theme discussed were performed. The job did not require review by an Ethics Committee, considering that the information regarding the legend of the subjects, such as sex, age and age were not collected, and all activities anonymously. The qualitative evaluation showed an active participation of the students worked on all proposed activities, with greater participation in workshops involving games. Of the 135 students who participated in the activities, 80 (59.3 %) delivered the completed questionnaire. With respect to quantitative evaluation, which diagnosed the level of knowledge about some aspects of sexuality theme in school who responded and delivered the questionnaires, 54%, 87% and 97% had participated in sex education class, they knew what they were STDs and felt important to use condoms, respectively. 58% knew what Pap smear and 91% thought important preventive screenings. 51% knew what HPV and 59% cited HIV as the most important STDs These data indicate that, in general, the information exists, even though verified significant rates of teen pregnancy or STDs contamination by adolescents in our country (BRAZIL, 1999). Several authors have reported low rates of adoption of safe sex practices among adolescents, despite high levels of knowledge. This diagnostic occurred in our midst, reinforces this thought.