1. Small Group/Youth Sunday School Curriculum- Regardless of what you may call it, you need a designated time weekly for the students to be a part of small group Bible study. Because your students need to be in the Word and growing in it if they are going to be able to live out their faith in this world. For this time you need a series of lessons for your students to study. It is not that your leaders and students could not just study on their own, but your leaders may not have the time to go out and prepare on their own to teach a Bible study from scratch. Plus this will help your students stay more focused as well as having your ministry focused on a more singular vision.
2. Youth Discipleship Curriculum- At some point your students need to take the next step in their faith and be discipled. Actually, this should begin immediately, and technically does if students continue to be a part of their ministry. But I believe there should be specific focused times for this where students are digging into a deeper study than in their small group Bible study as well as having an opportunity to share and deal with bigger issues. Again, a study is not mandatory for this but it does help to give some focus to the time spent between a student and the person who is discipling them.
3. Youth Ministry Sermons- You probably have a midweek service where students have the opportunity to come in for worship. A part of that time should include teaching as well so students can learn and have an opportunity to hear the Gospel. Granted, you could write your own sermons, and you may want to, but it is always nice to have a few extra sermons in your library in case you have a week that just gets too crazy. Some of you may even want to consider always using sermons written by someone else if you feel writing is not your gift or if you know the demands of your job and church are just too much for you to be able to find time to write and study.
4. Youth Retreat/ Disciple Now Curriculum-Occasionally it is good to have your students get a way for a little bit to refresh and refocus on their walk with Christ. You may just call this a retreat weekend or a more specific event name like Disciple now. Either way, this is always a great time for your leaders, your students, and for you. Usually as a part of this weekend there are a series of lessons and devotionals that students go through in order to spark discussion and help them grow in their faith. Four to six lessons is usually all you need for a weekend like this.
Remember that none of these particular part of your ministry "need" a curriculum but it is nice to have for focus, uniformity, and because many of your leaders do not have time to write and study along with the other responsibilities of their lives.
And remember something else, when you think about youth ministry lessons, sometimes the best lessons do not come from a curriculum at all, but instead come from the daily teachable moments like Jesus had with His disciples.