There is no doubt that sexual life is attractive and desirable for the great part of teenagers.Between the main factors that play the role in teenagers’ attitude to the sexual activity and thus create a general picture of adolescents’ sexual activity are biological, such as physiological processes in the young organism, and social, such as traditions and moral values of the society. The age of puberty varies and is around 12-17 years; it means that students in high school 9-12 grades are at the age of their sexual maturity. It would be logically to presume that if there were no limitations and restricts, all people would start their sexual life being high school students. Nevertheless, traditions and moral values of the society prevent schoolchildren from this step. It is widely believed that the later young person starts his/her sexual life the better is, therefore all the ‘coordinating power institutions of the society’, such as parents, churches and other religion organization, government, and variety of social organizations put all efforts to reduce the level of sexual activity among teenagers. Thus as puberty is an objective phenomenon and no possible reasons can influence it, traditions and moral values of the society are the key factor in the changes of teenagers’ sexual activity.The sexual activity of American teenagers is comparatively high. According to the national school-based Youth Risk Behavior Survey, that was held 15 years ago, more than a half of American high school students in grades 9-12 had already started their sexual life and a great part of all the students were currently sexually active. Thus the percentage of high school students in the USA that was estimated to have ever had sexual intercourse was 54.2%, and the percentage of those who estimated to be sexually active was 39.4%. Sexually activity means having the sexual intercourse during the last three months before survey (Sexual Behavior 1992). The same survey gives also the data about divergence in sexual activity in different race and gender groups. According to the report, black males were the most sexually active group among all the students. It is interesting that the number of male students who had reported to have ever had sexual intercourse was almost 12% higher than females’ (60.8% and 48.0%, respectively), and the difference in percentage between males and females who were sexually active was about 6% (42.5% and 36.4%, respectively). It could mean that either male students wish to seem more sexually active and report false data, or they have sexual relations with other than 9-12 grades female students, for example, other males, or those who do not attend high school, or high-school graduates. The difference in percentage may be explained also with the fact that sexually active females have more sexual partners than males. Multiple sex partners are considered to be the reason for concern. ‘Multiple’ – means four or more partners (Trends 2002). Surely, changing the partners frequently increases the transmission of (STD) and human immunodeficiency virus infection, which has negative influence (both physiological and pshycological) on the young organism and on the health of nation in general.High rate of adolescents’ sexual activity is the reason for concern for government. What is so attractive and desirable for teenagers is a source of national health problems for government. For a great part of sexually active teenagers, or those who rush to begin it, sexual life means adulthood, independence, in some cases the higher status, and of course, physical pleasure. For the picture of national health the meaning of adolescent’s sexual life is closely related to such phenomena as sexually transmitted diseases (SDT), human immunodeficiency virus infection, and unintended pregnancy. In one word, what is poetry for kids becomes a life prose for adults. That is why, a responsible sexual behavior among adolescents is between national health objects. The tasks of the government are to decrease the number of sexual active adolescents and a number of those who have ever had sexual intercourse, and at the same time to increase the level of students’ sexual literacy about sex, SDT, AIDS, pregnancy and the ways to avoid all the possible negative consequences of sexual life.As statistics shows, during the period of 1991-2001 the government succeeded in some of their tasks. According to the summarized analyzed data from six national Youth Risk Behavior surveys (YRBS) during 1991—2001, the prevalence of sexual experience decreased 16% among high school students, and thus was 38.2%. During 1991-2001, the prevalence of multiple sex partners decreased 24%. However, the total prevalence of current sexual activity did not change though decreased 12% among 11th-grade students and 23% among black students. At the same time the surveys show the increasing in condom use (Trends 2002).The changes in adolescents’ sexual behavior are obvious. The main cause of them may be the changes in teenagers’ views and moral values. Adolescents’ mentality – is a vary plastic material that can easily be shaped and changed, therefore if different institutions of the society will try to make an impact upon the mentality – it will work. Parents, families, schools, religious organizations, health departments, community agencies, and the media are the tools of governmental influence on the teenagers’ sexual activity and attitude to sexual life. Education programs provide adolescents with the knowledge, attitudes, and skills they need to refrain from sexual intercourse. For adolescents who are unwilling to refrain from sexual intercourse, programs help to increase the use of contraceptives and condoms (Trends, 2002). A great impact on the teenagers’ mentality the authorities of pop-culture may have. ‘Public’ people are the symbols of life success, desirable by everyone, especially by those who are only at the beginning of their life ways. Therefore public people are easily recognized as authorities, especially by those whose views are unclear and unstable yet. Many remember Britney Spears who popularized virginity before marriage, and surely thousands of her fan-girls followed her example.To understand the nature of changes in American teenagers sexual behavior we should consider the specialties of different race and gender groups and what has caused these differences. Why, for example, the total level of current sexually active students hasn’t changed, but the prevalence of current sexual activity decreased 12% among 11th-grade students and 23% among black students. It means also that sexual activity of white and Hispanic students increased. To understand these changes we may explore the impacts on the white and black students.Thus, sexual life of American teenagers as the national surveys show is rather active, though it decreased in some aspects during the period of 1991-2002. The reasons for changes may be found in governmental activity focused on decreasing sexual activity among adolescents and on the factors that change teenagers’ mentality.