I am not saying "kids shouldn't be told! Sex is a dirty thing of the devil! OF THE DEVIL!", that's straight ups retarded.
I am saying that like any good medicine, there comes a point where more is not better.
I am not saying kids won't have reproductive urges, and want to act on them. I am saying that giving them a message consisting of "we have many wonderful options to avoid those yucky pregnancies you've heard about! Here they are, and how to do them!" Is unhealthy.
A message more in line with "pregnancy early in life has a significant impact on how successful and independent you will be afterwards, and also on how healthy you will be later in life. Birth control exists, but is not 100% effective. Every time you have sex, you risk pregnancy and contracting STDs, and while every effort is made to ensure that abortion is safe, it too is not 100% so, and can and does result in permanent complications, including those that can only be solved with an emergency hysterectomy-- the surgical removal of the uterus-- in a small but significant number of cases. It is important to know that misuse of contraceptives such as condoms and birth control can dramatically reduce their effectiveness, increasing your chances of contracting an STD or becoming pregnant. The best option that you have to stay healthy is to avoid sexual contact. If you decide to ignore that sound advice, it is important that you know just what exactly it is you are risking, and what your options are."
Naturally, this latter one requires a pretty comprehensive sexual education package, and is what I advocate.
But going above and beyond that does not really help.