I think a lot of good advice is given here, but we all have to remember... we're not dealing with "grown up" logic... these are high school kids trying to get a rise out of him.

Some retorts to the single word comment "F@gg0T":
"No, I'm not a F@gg0t, I'm just expressing my culture. What? Are you ASHAMED of YOUR culture?"

"You DO know the 'style' of wearing baggy clothes came from prison uniforms that didn't fit, right? So you're heros are rapists and child molestors... THAT's cool (said with extreme sarcasm)."

(to someone who screamed it from a group) "I'm not the one trying to impress a bunch of guys, now am I?"

(to someone who screamed it from a group) "I'm not the one hanging out with a bunch of guys..."

"Actually, your mom/girlfriend thinks I'm hot" or "that's not what your mom/girlfriend said"

While the last one is juvenile, it is a deeply cutting insult to some.

The BEST advice is to continue walking or just give them an evil grin and ignore them.

I also agree with Steve... the BEST way to shut them up is to be a lady's man. The kilt will DEFINITELY give you an edge in this department, so USE IT!