Staying afloat in a sea of Apathy

For the past several years I've worked as an alternative education teacher during the week along with my ministry.  As you might guess, being in church on Sunday and in school during the week is like living in two different worlds.  For one thing, the respect and courtesy that makes our fellowship at Palo so sweet is a rarity come Monday morning.  It's also such a vastly different world in terms of what people care about in their lives.  For many of my students, there isn't anything beyond the next sexual encounter or use of drugs and alcohol.  Their lives revolve around these attempts at escape; some of them are self-aware enough to realize this, but many are so caught up in this "life" that they don't realize how hollow such pursuits ultimately are.  We as teachers are trying to instill the value of bettering yourself through education to students who are only tolerating us long enough to get home and get high.  Needless to say, in this environment tension runs high, animosity between students is frequent, and teachers shake their heads knowing that their own love of literature, history, or mathematics is not going to be shared.
Why do I keep working here (aside from the paying the bills)?  It's the rare students whom I have actually been able to reach, the ones whose lives I have made a difference in that keep me going.  These students are so very needy when it comes to kindness, understanding, and empathy that the little things that we can do for them can make all of the difference in the world.  I may only have one or two of these students in class this week; but they're worth it.  Reminds me of when Jesus said that he'd leave 99 sheap to go look for one that is lost.  These students may all be lost, most are fighting as hard as they can to deny it, but every once in a while we have one who wants to find their way home. 
All of my students know that I'm a Christian; most know that I'm also a pastor (they've seen me reading my Bible or working on my sermon while they're doing a reading assignment; plus I'm open and honest about it); they're shocked that I've never done drugs/alcohol, but in the end they can clearly see that my life is defined by things that they don't have.  If 99 laugh at me for not wanting to get high, at least 1 is looking at the hope that I have and wondering.