I was at a Biotechnology high school flunking badly because I spent more time in theater, cultural centers and all places humanities people go instead of science people. It would take an year and half for me to "get" what was going on.
Cultivating my platonic crush on the short, curly-haired brunette tap-dancer/ballerina girl from my classroom;
Hanging out with the other nerds;
Playing Vampire: The Masquerade with a Malkavian, in high expectations for Changeling:The Dreaming, and power-playing psionics on AD&D 2nd Ed.
Practicing Hung-gar I suppose;
Playing video-games in the Commodore Amiga 500 and in my old MSX, while at the same time despising all things PC;
Watching anime on VHS tapes that were copies from the copies a friend made from the copy of an original Japanese one. That was a black market and no cool nerd would watch just the one or two that were on open TV back then;
Studying Kardecist Spiritism;
Practicing hypnosis with friends for fun (don't do it);
Having my first job not with family and not in school, where not only the gay boss would try to hit on every newcomer, but the girl I liked there (not the same crush from school) thought it would be a good idea to use my name to make her Jiu-jitsu fighter boyfriend jealous. Eventually a new guy arrived, the girl I liked left and I think the following year I had already changed jobs.
The first year I sported long-hair, I think.
And basically not at all aware that I was already a young adult.