9th grade Girls....wow!

I took 3 of my youth group girls out to taco bell tonight for fun. They are all freshman girls. I guess I don't really need to say more, but I will. So what I don't understand is a couple of things right now, 1. why do they always giggle about nothing and then when you ask them what they are giggling about it is too embarrassing for them to tell you? 2. why do they never ask me any questions?....ya know a one way conversation is hard, and frustrating!