The Fenway Community Health center in Boston publishes such a survey every other year. While it is important to be able to respond to the religious and political right, a lot of the time your words will fall on deaf ears. But, just in case, it is not a bad idea to know first-hand the Bible passages that will be thrown at you. Sexual orientation is one's identity in the world. It helps define a person's attractions and romantic interestes.
Sex is sex.
When we see straight people we do not reduce their identity to what they do behind closed doors. You can have a notebook available for youth to enter their testimony. Teachers, parents and others can be advised to do the same. Have an adult or a youth write an anonymous letter to your local paper describing in detail what it is like to be GLBT in that community. It is very powerful.