101 - Cs in any subject won't help your application and I don't think repeating a class will wipe out the old grade. The bigger picture is your overall grade point average and the difficulty of the courses you've taken. Remember you are competing against a lot of applicants who are in the top 10% of their class. Scholastic ability is not the only factor in admissions but it probably takes some pretty strong athletic or leadership abilities to overcome average grades. You can't change the past so keep the focus on taking challenging courses. Talk to your school counselor regarding the type of courses you should be taking to have a shot at USNA or other schools.The hard work that you put in now will pay off for you later in college and the work force whether you get accepted to the Naval Academy or not. Good Luck!