1. Students need help fitting cultural trends into their lives. A good student ministry should be tuned into students and the latest trends, music, and other junk. Students can be easily blinded by the flashy draw of the latest cultural trend and not have the spiritual sense to see the enemy's ploy to steal, kill, and destroy them.
2. A good student ministry will speak the hard things. Now, as a parent you should certainly speak to your child about the hard things - especially sex, & other tough stuff, these things are way too important to leave up to a student pastor or anyone else! However, we have learned that their are a lot of things that parents assume kids know, or just didn't realize they needed to say. For example, apparently, Bill Clinton's parents neglected to properly define what sex is - I am always amazed at how many kids have a similar view, if you catch my meaning. A good student ministry will be prepared to offer straight answers for students on a variety of topics.
3. A good Student ministry no matter how small, will offer some non-parent role models. They should have the opportunity to see these leaders interacting with God, sharing their faith, serving, and displaying the joy of the Lord in various circumstances. Ideally, they need to see others applying and considering spiritual concepts to their normal lives. You've heard it said that, "You are the only Bible most people will ever read?" That goes triple for teens - they need to see lots of walking Bibles in their lives to see that faith is real and it can be lived. Hopefully, they are walking with their parents and seeing these things too, and the influence of these other people will just be the icing on the cake that helps them develop their identity in Christ.
4. Students need CHRISTIAN community, a group they belong to and feel comfortable with. WAY, WAY too many Christian kids turn to an unsaved friend or worse yet, the Internet or Facebook when they have a problem. They need opportunities to get face to face & comfortable with a group of peers and a leader, be encouraged, be supported, and cry or work through problems with a Godview.
5. By-golly Students need to SERVE! They need to get off of their lazy technologically driven hineys and work. They need to sacrifice and give of themselves and submit to the authority of others, humble themselves for a greater good, and be needed. I think every student should go on at least one mission trip during their high school years - better yet one a year.
Whether you are in a church with a youth group or not, I hope you will analyze where your teen is headed and really be intentional about raising them up to have a faith that lasts. If you feel that your youth group is not meeting these needs, by all means, get yourself involved and make sure it happens, be the change. I've never met a youth minister that shunned help.