"Don't sacrifice what you want more for what you want now. Write down what you want the most and see it often." ~ Peter Vidmar 

If you want something in life then work for it. You should also write them down in a book and try to accomplish your goal. You need to give up on things that you don't need and go for the goals you do need. For example, if you want to have straight A's but then you also like using your phone and watching television then I suggest that you give up on the using your phone and television. Therefore you should focus on the thing you really want which is having straight A's, you will have more time to study and accomplish your goal. Or if you want to be on a team ad your are still in school and you have tons of homework assignments due the next day then you will need to find a way to balance your schedule and make it work out.