Mission is, in fact, a quite apropos way of phrasing it; Leo's used to thinking of most things that way, especially when his presence at the school in the first place was framed by Splinter in terms of go learn these things. Duty is an easy frame of reference to apply to most things in the world.

"It's...still about perspective, I guess. There's been some trouble brewing with the criminal underground in New York and some research on the x-gene. My family kind of stumbled into the middle of all of that, but somewhere in the middle of dealing with it, my father started thinking maybe we need more perspective about what's happening everywhere else, too. And since I need to learn how to control my power anyway...this seemed like a good place to learn. So I guess it's not so different from why you're here - getting perspective on what I haven't been in a good position to find out until now."