Be sure to check out the video my husband's company produced:
30 Hours of Chalk from M4 Creative on Vimeo.
Here is the video featuring Clayton in the 2011 Chalk Festival:
Chalk Art - from Christopher M. Jones on Vimeo.
P.S. Never kneel for 30 straight hours with knee pads strapped on...apparently it causes nerve damage. We are hoping the nerves in Clayton's leg will repair over the next couple of years.