Hey
High School is cool ahah.
I remember back in the days of high school I only f-closed three girls from high school (lot of k closes and handjobs etc).
I remember that negging them is really useful and If i knew back then what I know today I would have closed much more ahah.
The comfort is really important, since you are from the same place, and you gonna see each other everyday, work it in a nice way, DHV, and brink the most of your social person and cool guy.
Don't act AFC by texting her all the time when she doesn't answer, just don't care. Act like if she doesn't matter and like you don't wanna fuck her at all.
I used to bring girls to my house 2 mins away from school, for lunch ahah. Watch a movie and make out. f-closing is a bit more difficult. Either you have plenty of comfort or it's gonna be though. I remember back in the days took me 3 months of making out to f-close my girlfriend at the time..
Be the Social cool guy. Have parties at yours etc... Act like the guy that knows everyone, and all the girls talk about, be difficult just like they are, make it seem impossible for them to ever date you.
Don't know if it helped. Hope at least you got some ideas for the future.