For those of you who might have some experience, what do you see as the dynamics of speaking to a large group of teens compared to a mixed age congregation?

I am speaking to a gathering of about 100 teens and young adults at our church next month.  My plan is to to use lots of personal experience, biblical themes, and challenge without reading more than perhaps one text right out of the Bible.  The rest I will retell.

Any advice on communiation? Honestly, I expect that we could all learn much about communicating with adults from our time with teens.  I suspect that they are not that much different!