Goals can be great, but I am not sure the actual # needs to be your main focus - or that a 3.8 has any real meaning.
- Improve your grades each year, especially in math.
- Get involved with a couple of things you love to do, and do them with passion.
- Prepare for a test-required environment by preparing over the summer, when it is less likely to interfere with your grades.
Agree that Stern is a very tough one, but you will have a bunch of options if you stay on track.