I'm leaving high school, so I might as well tell you how to pick up girls in high school. You won't be hitting on me!
REPUTATION. Your rep precedes you, even if you don't have one. To pick up girls in high school, you need a good reputation. So you have to lay the groundwork before you even start talking to chicks, get it? Be excellent at something, even if it's math team. (Of course athletics is better, but if that's not your thing, then don't try to make it!)
WORK YOUR WAY UP. This is how high school (and the world) works: Boy wants girl he can't have. Girl wants different boy. Boy tries to befriend girl so girl will see the truth. Girl puts boy in friend zone and will never go out with boy. After you have a positive rep at something and can get a date, take dates from girls who want to date you and work your way up the social ladder. The second step in how to pick up girls in high school is that there is a very real totem pole to climb. You don't fight the enemy boss at the beginning of a level in a video game, do you? So you don't necessarily get the hottest girl at the beginning of your dating life. To pick up girls in high school that you want, respect the environment, date on your level, show them a good time, and work your way up.
TREATMENT. Girls at the top of the totem pole know they are at the top. So until you get within striking distance, this isn't going to work. But after you do Steps 1 and 2, the top girls will start to look at you differently. You are now a sexual being worthy of a chance. So how do you treat them once you achieve this? EXACTLY THE SAME AS THE OTHER GIRLS. Knock them down off that pedestal. Whatever you did to pick up the lower rung girls, do the same thing. Did you flake on them? Then do that to the hot girl. Did you ignore her texts? Were you super nice? Whatever you did that worked, don't change it for any individual girl. Girls are all the same, really. To pick up girls in high school, remember that the girls on top are only there because they are believed to be there. They are just as insecure as the girls on the bottom, maybe even more so. Use that to your dating advantage.