Not sure what teens like....they aren't allowed in our house (LOL)!!
I would serve an antipasto tray with veggies, olives, mozzarella chunks, breadsticks or melon with prosciutto, salami curls....whatever you think they may like.
Salad, garlic bread, and lasagna...sounds like a plan! Add some wonderful dessert like spumoni, cannoli, tiramisu....whatever works for teens. Our local grocery sells all kinds of mini desserts...if you have something like this near you, you could get a nice mix.
Good luck.....buy some chianti for mom after the party!!