"Be interested in what interests me."
Teens often feel their parents don't understand them, because they don't. We grandparents, having raised teens, possibly understand them better than their parents, and we know, thanks to our unique position, what we need to steer them away from and what we can nudge them toward. If our grandkids have an interest we're concerned is not good for them — say, violent video games — there's lots we can do. We can try to interest them in a better hobby or buy them nonviolent games. And if we can afford to pay for something that might have a more positive influence (even drum lessons!) or some other activity involving live people who don't hurt each other, then we should do it.