I agree on the confronting, however, I can't - I mean I know myself and I'd probably hit her - well not really, but I'd say that would only encourage the thoughts of bad influence....sorry but I can't be that nice - the protective mom thing.
My husband is planning on talking to her dad though - my husband knows him a bit through various kids activies. I don't know the "witch" much - other than through school - she is a teacher's aid as well at the school. Fortunately she is no longer in either of my kids' classes - she is with the pre-schoolers and kindergarteners.
It is possible that this girl's behavior is being blamed on my daughter. My daughter hinted that this girl has more recently been getting in more trouble at home. To me that is normal she just started high school - the age thing. And the hint is - my daughter's influence.
She also seems like she doesn't get along well with her mom. She is always telling my daughter how her mom is mean to her, that your youngest sister is spoiled and gets all new stuff and anything she wants, while she doesn't. Her brothers can be on the computer whenever they want, but she is limited with time. I realize that this kid is probably exeraggeted this - what kid doesn't - but there is definately friction between the two.
Funny you mention about popularity - because of course on the positive this opens up conversation - I told my daughter how I trusted her to make good decisions. I would know even if she was around kids that may not make the best decision, that I trusted she would make the right one. So I would never do this to her. So maybe she thinks I am permissive, but only because I know my girl and she has only shown me that she does make good decisions.