Piano Lesson Nightmare

This family that I teach piano to has 3 students in it: the mom, and 2 daughters ages 12 and 10. The mother stays for the older girl's lesson and yesterday we had a little episode. I don't like to criticize other parents parenting styles. I just try to find things in them that I like and want to implement into my style or things I personally would like to avoid. So this story is not meant to criticize but only to learn from other's personalities. This girl sat down and played a song that she is working on on top of her regular lesson material which I call "extra goodies." After she finished, I started to give her suggestions on how to help her play it better. The girl started playing with her rings and when I finished she said, "Look I have a tan line from my ring..." and started talking about other things. I ask her if she was listening. At the end of the lesson, I was talking to her about practicing because she had practiced her "extra goodies" but not her regular material. She didn't listen to anything I said and before I finished she got up and started to walk away. Her mom said no go sit back down till she is through. So I continued and she interupted me halfway through and started talking to her mother. I said you know what we are done. The child left and I talked to the mother explaining that I don't have to deal with that kind of behavior.

After a night's sleep to cool off, I have decided a few things about this situation. As a mother, I think I would have handled the situation much differently. I would not tolerate any such disrespect to my children's teachers. As a teacher though, I have to make decisions about how lenient I am going to be on practicing, paying on time, and disrepect. In general, I would say I am pretty easy going on most things. I wasn't lecturing her on how much she needed to practice or how long, I was simply saying that she needed TO practice or she wasting my time and her mother's money. I do think that disrepect is no tolerance issue. Now I don't have any teenagers or even pre-teens who think they are teenagers so I am not an expert on their behaviors. Perhaps I am being too hard on her but I seriously considering dropping them from my studio.