How the hell do you get teenage boys to care?

My father is a 100% disabled retired veteran who works 12 hr shifts (1 hour commute ea. way). And he's trying to raise two teenage boys on his own. Their mom is a hoodrat with no ambition and their older brother is a high school drop out whose probably in prison. Who knows?
I dont know whether to be apathetic and let them learn on their own or to be like the single mom's out here dating a man who can be a father to their kids.
My brothers are 14 & 16 and barely getting through school. They are so lazy and unmotivated but I don't blame them. They have no structure. I had to finally take out the trash that was overflowing, while they sat there playing video games.
I cant raise them, I'm only 23 and we are not even close. But it could be a thousand times worse. At least if they hit rock bottom maybe it would wake their asses up, and they would hustle but they are sheltered from it. It's like watching a car crash or a ticking time bomb.