According to the article, the one element that has varied from the past in our contemporary era is marriage: marriage is delayed and, if social patterns are accurately evaluated, feared. Perhaps the question is how to bring marriage back into vogue.
I think there is a consensus here that Christians should continue to teach abstinence before marriage. In fact, that is the only thing that they can do, if they value either the Bible or tradition. To teach anything else would be to go against both. They may package this teaching in a different way that would make more sense to young people, but they should continue to teach it.
Christians - and others! - should absolutely continue to work on discouraging casual sex. I believe, however, that they should emphasize the emotional aspects more. When groups focus on STDs and unplanned pregnancies, young people have the perfect counter argument by saying that they use condoms and birth control. No one seems to deal much with the emotional consequences of casual sex and of young people engaging in activities for which they are not developmentally ready, and this is important as well.
I think we are now seeing the consequences in society of having lots of relationships that involve sexual intimacy which do not involve a deep, profound and lasting commitment, especially where children are concerned. I do therefore think that Christianity is at least right in trying to convince couples to wait until they are married before having sex, because the consequences otherwise are rather terrible to contemplate.
I agree with the earlier folks who suggested that persons should be discouraged from having sex until they are in truly committed relationships. The consequences of having sex outside of such relationships can be unfortunate for everyone involved, especially if "everyone" includes children who are born out of wedlock.
Christians should absolutely not stop trying to convince children to abstain from sex until marriage if that is part of their belief system. However, young people who don't shouldn't be ostracized or degraded because of that choice. Ultimately, I think the best sex ed is information. Be honest with kids (and if your beliefs dictate it, this means telling them the religious implications of their decision) and support them either way.
I believe Christians should concentrate on teaching their children that sex should saved for a committed relationship instead of the casual "hook-ups" that so many young kids engage in these days. I think most teens view the idea of waiting until the wedding night before engaging in their first sexual encounter as both unrealistic and antiquated, though I'm sure there are many dedicated Christian teens who will strive to achieve this goal.
Just because some teens and young people don't wait until marriage doesn't mean that the message should be abandoned. If the message of abstinence isn't out there at all then what message is being sent? Having an abstinence message on "one end" of the spectrum allows for a conversation and allows for other positions along the spectrum. I would like to think that it gives young people something to think about before they make a big decision about their sexuality.
Why would they stop trying? While it is true that statistics suggest a majority of young people do not wait for marriage, this does not change the fact that it is a Christian value to abstain. Values aren't sacrificed because they aren't adhered to by a majority.
I do think a shift in the approach of the abstinence-only crowd would be more effective. Teens do not react well to the scare tactics often used by adults, because at that age they still feel invincible, and associate behavior more with reward than consequence. Appealing to the value aspect more than the fear aspect might get better results, in my opinion.