"Picking" up bad habits

Yes, I'm afraid Bailey has learned to pick her nose. I'm not exactly sure when this happened, but one day I looked over at her, and there she sat with her finger up her nose! No, this isn't a pleasant topic, but one every parent deals with at one time or another (or at least that's what I'm telling myself!). This grosses me out big time, but I try not to make a big deal out of it, because I know the worse I make it seem, the more intrigued she will become with the whole thing! So, I try to just tell her "No touch", when I see her digging for gold. Most of the time it works. However, my daughter has somewhat of a brazen streak in her. One day at lunch I had already gotten on to her for this, and the next thing I know she is staring me down while slowing putting her finger up her nostril, almost as if she was thinking "What are you going to do now, mom?" I had to turn my head to laugh before I told her "No" again. And this isn't the only time she has tried to test me. Lately it seems like she is seeing exactly what she can get away with. She'll do something that she KNOWS is not allowed, and just watch me the entire time!!! I can only imagine what the teenage years are going to be like!!