GPA, do I have hope (its not that bad but I need advice)?

OK im gona give this too everyone fast and simple to understand. My Gpa is about a 3.0 - 3.2. I am in 10th grade, I want to go to Kings Point (united states merchant marine). I plan on doing very well on sat ( sorry for bragging but ive got nearly 100% on all the pre tests and I get about 95% to 100% in all my midterms and finals, im a great test taker) My trouble is in marking period grades. Do i have any options, how much can one year take me up? What colleges can i get into. Thanks Bern