Youth ministry 36o is one of my favourite sites out there. Make sure to check out their free lesson on valentines day. Here is some more info on the lesson:
Lesson Title>>> AMAZING LOVE: Finding And Living Real Love
Lesson Objective>>> To help students contrast the world’s idea of love with the real examples of love found in the Bible.
Scripture Focus>>> Ruth 1:16-18; 2:8-12; 4:9-15