Here's some snack ideas:
Sliced Pepperoni & string cheese.
Celery with sugar-free peanut butter & cashews

As far as teen friendly meals, I enjoy doing what I call Plate-o-Pizza. Get a big oven proof plate and slather on just a little of some LC spaghetti sauce. Cover with shredded cheese, pepperoni, italian sausage, onions, peppers, tomatoes, herbs, etc. and bake until the cheese is nice and gooey. It's so good, I don't even miss the bread!