You don't want your kids to know they have a choice? ? I think that is a well rounded education, giving choices and explaining choices. Giving both sides and going in depth about the consequences both sides may or may not have. Granted abstinence is a minority opinion, that doesn't mean it doesn't need to be touched upon.
To many it is not a moral, a religious commandment, it is simply an option. 2 options, have sex. Don't have sex.
In the SF public schools they taught us everything that was then current about safe sex, and it was covered in middle school (grades 6-8, ages ~10 thru ~14). And yes, they drilled it into our heads that the only way to be 100% safe is to abstain. They also left each and every one of us knowing how to protect ourselves, where to get condoms and other birth control for free and free of judgement or harassment of any kind.
An interesting thing to note: when I had these sex ed presentations in middle school, they were always done by people from the local teen clinics. Folks not too much older than we were. Folks we could relate to. And, part of the agreement between the school district and the clinic was that the teacher had to stay out of the room for the entire session. No fear of judgement or harassment or the discomfort of dealing with Mr X, Ms Y, or Mrs Z who we had to see on a daily basis in class.