I think everything should be taught in school. In our town the Catholic school combines with the public school after 8th grade. The private school kids are always more curious and ready to try everything they aren't taught about. They see it as being popular to do these forbidden things, while for the public school kids are taught about sex and drugs and don't see it as a popular "rite of passage to do these things". I think that sexual orientation should be taught as soon as regular sex ed because it is something that people need to understand. Condom samples, usually end up a balloons anyway, are ok because there are a million places for minors to get them if they really want.
I personally don't see anything inately wrong with premarital sex, it is the person's choice whether or not they plan to stay together anyway. What if they get married for the weekend just to have sex and then divorced, they still had sex regardless of whether or not they were married, nothing changes in the way of how many partners they had. If somebody wants to risk disease or pregnancy go ahead, I don't care I'm not sleeping with them. I prefer to leave responsibility and consequences up to the person, me and my boyfriend have both been tested for std's. Anyway, I think waiting till you are married is getting outdated and I don't see an arguement for it or against it. I don't think premarital sex is the cause of unwanted pregnancy anyway, its a personal thing, there are plenty of people who have premarital sex and use protection responsibly.