One of the biggest challenges for a picture book author/illustrator is to come up with a compelling story that can deeply involve the reader without using words. Think of David Wiesner's Tuesday
and Flotsam (Caldecott Medal Book)
-- two great stories with pictures so rich and detailed that words are truly unnecessary.
Bill Thompson brings the same level of artistic skill to Chalk. After reading it, I wanted to re-read it to get a better idea of exactly how Thompson carried off such a rich story in so few pages and with only his images.