Current Junior in High School, how much improvement on lsat?

Hello all! I am currently a male Junior in high school, and I am interested in attending law school. I recently took a practice exam - http://www.lsac.org/jd/pdfs/SamplePTJune.pdf , and I scored a 164. How much improvement could I expect from now, until it is time for me to take the official lsat? If it is any help, I scored an 1870 on my first attempt at the SAT.

You seriously need to chill. Get into college first then we can start talking.