Not something you could do in class, but if you learn to shave with a straight razor, that's instant, undeniable man-points. Almost nothing is as manly or as ballsy as saying "hey, I want to get rid of the hair on my face. I'll just cut it off with a fucking knife because fuck technology."
You could always take up poetry--depending on what you're going for in terms of "badass" this could either be a terrible idea (either you're a terrible poet, because some people just are, or the suggestion itself is not at all what you were looking for) or a great one, because a lot of people with a brain will respect decent poetry/writing. But that depends on people around you having a brain, something I cannot speak on or assume about. The major upside to this is you can do it basically anywhere and if you get good at it, you'll be able to win rap battles on the fly. Hell, I can basically speak in iambic meter if I try a bit at this point. Not quite to the "rhyme like a boss" part yet, though.