Should we have to say something we dont believe in?

I am a 16 year old boy in Delaware, and my teacher says that we have to say the pledge of allegiance, but I reminded her that there is a passage in the Constitution that says we dont have to if we dont want to. Now, the part i dont believe in is the part that says "with liberty and justice for all" i dont believe that is what America really stands for because we still have racism, high gas prices, rich not having to pay taxes, illegal aliens getting drivers licenses, etc. And until this stuff is resolved, hopefully by Obama or Clinton, I will not and cannot say this part of the pledge of allegiance. If they want to take God out of it because they dont believe in it, then we can take out stuff we dont believe and I need your voice!