I don't think she is really going to call the school. If she does she needs to really find something to do in her life. She probably said that to scare you and to get you to stop talking to her daughter.
Im pretty sure she has much better things to do then go to your school over something so little!
I'm not sure how strict your schools is on bullying (or if they would consider it) The only other thing I would suggest is writing to your friends mother explaining the situation and apologizing for any misinterpreted wrong doing. Good Luck!
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.