Motivation and discipline are complementary aspects in accomplishing your goals. Some people seek external validation for discipline and motivation and some set up these goals intrinsically. As a high school student you should be on your way to become more independent. Adolescence is a preparation for adulthood. I am sure you are looking forward to driving, going to college, doing things independently etc. So make a check list of your values and then set up your goals. I am sure you have a many strengths as well as weaknesses, evaluate and see what gets in your way and use your strengths to minimize your weaknesses. Your mom can monitor you definitely but try being more independent. When you set up your goals, take small steps first and then when you succeed with your small steps, enjoy the success and keep moving towards your higher goals. Good luck!