In high school I spent most of my weekends writing computer programs or if I got stuck I would play a video game (though no so much, I had almost completely stopped playing video games by my junior year). If I wasn't doing either of those then I was probably at a neighbor's house fixing their computers. I guess I also watched TV back then, back when TechTV was still around and there were great shows like The Screen Savers.
Didn't really play any musical instrument at the time but I really got into Creedence Clearwater Revival around my freshman year, then Crosby, Stills, Nash and Young my sophmore and part of junior year and then The Doors to finish out high school.
Oh, and playing around with the family dog was always fun! 
_________________
((12+144+20+3*(4^(1/2)))/7)+5*11 = (9^2) + 0