Calling all experienced teachers

I am a student teacher and I have a 9th grade English class. I'm stuck. We have a highly modified curriculum which has all the lesson plans for every day. My students say it's boring. I want to give them some choices because it's their senior year, but the only problem is that I don't have any of their scores on this curriculum for this year yet, so the principal told me to direct-instruct the same lesson plans. Did you have to modify lesson plans when you started as a new teacher? How did you get the principal to unhook you and let you experiment with different lessons plans? Thank you...I really want them to have a great senior year.