Answer:
I believe your teacher would like full sentences so like "I want to become a better student by next week" or I will try and become a proffesional athelete by the time I am 18 years old.
They are poorly written goals because first you need to have a whole set up, how your going to achieve them. Second, you can't achieve these goals only for once. A shows only one week, why not always? B is complicated since you have to be really good at athletics and take very advanced courses at a young age.