Use this collection of Bible studies as a template for your next youth retreat or as a weekly series to cover some of the common spiritual disciplines.
When I did it, I called the retreat "Monk Training" and provided an opportunity for students to practice each discipline immediately afterward. You can arrange the discussions and activities in any order that best fits your needs.
How to Bless Others - encourage students to find ways to bless each other and give students an opportunity to share how they were blessed throughout the weekend
How to Worship God Physically - exercise afterward and make nutritious meals together throughout the weekend
How to Pray - lead a time of prayer by following the steps outlined
How to Fast - fast one meal (I recommend fasting lunch)
How to Read the Bible - lead a time of Bible study by following the steps outlined (I let each student choose their own passage and go through the steps silently to themselves)
How to Worship in a Faith Community - lead a time of worship appropriate to your tradition or practice
How to Engage in Theological Learning - allow students to brainstorm questions they might have and then let them ask you about anything that comes up
How to Take it Home - use this as part of your closing session