Does this sound like a good highschool application essay?

Not bad, Hanna. Here are a couple ways I think you could improve it:

1. You gave only one reason why you want to go to this school: “I grew up with, and enjoyed the private school system.” It’s a valid reason for you, but one that they might not find so persuasive as a reason to admit you. You then said that another reason is “I know it is the best school for me at the moment,” but you did not say why. Add to your essay a brief statement about what makes it the best school for you (different from the one reason you already gave).

2. You named a variety of activities in which you may have some enthusiasm, talent, and skill, and you identified those, too, as reasons why you want to go to this school, but they make more sense here in response to the other question for the essay, as gifts you will contribute to the community. However, the question asked for one unique gift. It’s fine to leave your whole list in (if it doesn’t make your essay too long), but you should emphasize one of them and say why you think that is the single greatest (or most unique) gift you would be able to share.

Good luck!