Certainly not all 16 year old (or any age) boys (or girls) are having sex, and those who choose not to should be respected. They are often going against both desire and peer social pressures, and that takes courage and integrity.On the other hand there are many who do, and people telling them not to will make minimal difference, especially if it is no more than a dogmatic assertion. They also have made a decision, and they also may have courage and integrity.