I love my best friend but Im sick on her talk about drama?

Ok. Allie, my best Friend who i love to death, goes to school, I am home schooled. I love talking to her and hanging out, but I am so sick of listening to her talk about the drama going on in school (11th grade for cryin out loud!) We're going to a concert on saturday and i just know drama will be 90% of our convo on the way there. I want to tell her before the concert but IDK how. help ? :)