Motovation to p high school?

im 14 and i just failed the 9th grade with 0 gpa the reason for this is that i think school is useless from this point on, school teaches me all this stuff that i may or may not use in life and it irritates me that im wasteing my time with it and that i just cant get a job,but the world dosent work like that,and i need a stupid slip of paper to get 1, i want to become a cop or a fireman and help others and i dont think that learning algebra and how to cut open frogs to see how stuff works is gonna help me in that goal.all i need is to be psychicaly fit,have common scense and logic which i have. please help me out...prove me wrong about this because knowing that im gonna end up homeless is just not enough motovation for me. im a person who lives for today and dosent think about tomorow until it comes. i really need an awnser on this guys