How do I respond to being called “Jet Li”?

I work with minority teenagers in NYC, many of whom have very limited interaction with people outside of their race and ethnic group. The large majority of our kids are fantastic and great to work with. But I continue to encounter a phenomenon that I call the "Bruce Lee taunt", and have not come with an effective retort.

In the hallways of a high school, it's not uncommon for kids who see me to shout out something along the lines of : "Hey, it's Jet Li!" or "Do you know karate?" or "You look just like Bruce Lee."

Certainly not the worst epithet one could be subject to. But not one that is likely to endear them to other Asian people they encounter.

Given the realities of being in the hallway of a high school (not much time, lots of kids around, etc), what would you do to address that kind of question or comment?