What I meant to say is that unfortunately there are those out there in the deeply religious communities of all forms (Jewish, Christian, and Islamic) that believe that they will implant ideas of Impurity (knowledge of the sexual organs and their function). This would then cause them to have sexual relations, as the saying goes.
This is all a logical fallacy. Just because a person has knowledge of illicit drugs and their effect on the human body does not mean that he will partake in it. It takes much more than knowledge for someone to go about an action. Hiding information in this day and age will provide more harm than good. He or she will be made a laughing stock at school and will hear incorrect information from their peers. So if a parent is going to be absentee on this issue, they are setting themselves up for a possible disaster. You will make your child an outcast, they will not have a good sense of self, and they will resent the parents for it. When the child is in the above scenario that is when they start to experiment with things, things they do not fully understand.
That is just my 0.02 cents