Every year, our school has a Sidewalk Art Festival where students sign up, get a box of chalk, and do a square in the park. Unfortunately, it's the only chance I get to use the big, honkin' pieces of chalk, so I've got no experience, but I tried, on my post-concert high to share the love that is GBS(everyone who knows me knew it was mine...). Because none of the reference pics I printed out for Bob had a good enough shot of his face, the role of "Bob" will be played by "Random Guy with a Fiddle and Annoyingly Red Hair" (chalk does not behave like colored pencils/paint....)
Anyway:

Yeah.
"This is magnificent -- and it is TRUE! It never happened, yet it is still true. What magic art is this?"