How do i get lead/supporting roles in non african american based plays?

i am a 15 year old female that is african american. i have been involved in theater for 2 years and only have been in the ensemble for both plays.. they were bye bye birdie and how to succeed in buisness without really trying. white people plays i guess. i'm taking acting cles and getting better. i want the chance at a supporting role or lead in the next play at my high school: the pajama game. how could i get the role of babe? ususally the main character is white and the only plays i think i'll ever get a main role in is raisin in the sun or the color purpl because they're african american based plays. i want to be able to get a lead in a non african american play so how do i do that?