Have you ever brought in your computer (if you have a laptop)? Pictures, music and videos can be that much more interesting just because it's on a computer rather than a more conventional medium.
You could also try simple dating ideas to spice up the lesson. Don't feel like you have to teach every bit of the manual. Pick the part that holds the most message for the youth and just have a fun moment with that - have them make construction paper costumes or act it out (write up scripts etc.)
Maybe have a fish bowl discussion - this is where only 2 people get to talk and they sit in the middle discussing the topic at hand. If someone else wants to participate, they tap one of the two people out. This works best when it's an ambiguous subject that has grey area like how much of a kiss is inappropriate (although hopefully they are not kissing at all yet).
Sometimes it's worth bringing up a scripture, explaining the lesson learned from the scripture and then just talking about that lesson rather than making sure they know the story or they've memorized the scripture.
So does this help? I can probably be a better help if I had a specific lesson/scripture.