Seems like that being the intelligent little girl that she is - she has figured out a way to get attention. She must be learning this behavior from somewhere. Its not something that a kid can just suddenly pull out of the sky. And since it gets a reaction, she keeps doing it. Ignore it, and it should go away over time. Also once she starts school, it will be unusual enough that I am pretty sure the behavior will stop due to peer pressure.
But, I am curious. We also have a child behavior forum here -
http://www.medhelp.org/forums/Child-Behavior/show/64
where this would get more attention and more responses. Did you post here because you think she also has ADHD? Because that would change the answers.