I think I made a post recently to the effect that society floods culture (to kids and adults alike) with messages regarding sexuality, including both messages to enjoy it and messages to control it, but both point towards obsessing over it. The mere flood of messages (in both directions) make sex a matter that kids (and adults) more regularly think about, and this contradictory nature probably makes something like sexuality a jarring issue for kids (and adults), tending to make them vulnerable. A few points:
1) Sexual behavior by kids is nothing new. Sex probably happens more outside of marriage now, but one must also give consideration to the fact that many people do not adhere to this particular institution (whether by choice or by the law), that people who do marry tend to do so later, and that many people do not see a moral reason to abstain outside of marriage (again, if the institution is even in their plans). Some of them lead to very reasonable circumstances for sex to happen outside of marriage, but traditional moralists tend to not recognize this idea. Also, people tend to not stay in abusive marriages as often or as long now, particularly since women tend to have greater autonomy.
2) Boys (11%, I think) and girls (17%, I think) alike do not tend to be virgins if/when they marry, so certainly the idea of virginity is the exception rather than the rule.
3) The messages of sexuality tend to fairly polarized. Sources that advocate abstaining from sex also tend to advocate abstaining from masturbation, much less approving it. Those sources also tend to be hush-hush about safer sex practices (condoms, other contraception, alternative sex acts), which means that if abstinence doesn't hold up (and it's at most slightly more likely to), then the sex will tend to be significantly riskier than under other circumstances.
4) As mentioned in the article, the burden for sex and virginity is placed on the women. As mentioned earlier in the topic, there aren't many purity balls for mothers and sons.
5) Discussion of sexuality tend to rely on emotional arguments rather than objective, verifiable information. Whether it's the purity police (whose belief system often rests on an intangible "God" and who seek to hold power over people) or the mainstream entertainment industry (who care ultimately about profit), they tend to cite scientific sources only when it suits their cause, and they tend to present their results in misleading ways (such as assuming causality when only a correlation is shown).
Responsible sexual behavior requires an acknowledgement that sexuality, like with countless other activities, is best excercised with discretion backed up by self-efficacy. One should identify a risk level they fully understand and can be comfortable with, and exercising their sexuality in ways that meet the necessary prerequisites of all parties involved and respects the right of consent at all times. There is still a place for virginity until a relationship achives a certain advanced level of commitment (I'm a 28 YO virgin myself), but the idea isn't to stake one's entire identity to it. One's choices, even sexual ones, should arise from their identity and values; it's not the other way around (even for, duh, women).
It can be as simple as basic playground rules, but some people's lack of imagination leaves them in the 19th century.
