Oh boy. 
I think basically it comes down to moving them. I'm a sophomore in high school so I'm struggling with this but I am trying. If electrons are moving freely that's electricity I think, so she man make/stop currents, and if they're whizzing around an atom then the most she can do is change their energy level. She can't remove electrons from an atom, but she can sever or create atomic bonds. I should probably make an edit or two. Magnetism I understand a lot less, I've been told it's the same thing as electricity but that makes no sense to me so I probably won't be focusing at that at all.