In one activity, we drew a chalk number
line on the ground where students physically moved their bodies along the line to learn about integers.
It refers to a chalk number
that is assigned to an aircraft and the corresponding chalk number
given to personnel, equipment, and supplies that will be loaded on that aircraft for transport.
Each bore a chalk number
to denote its former owner.
Close inspection of the work reveals it sits on a grid of white chalk lines with corresponding red chalk numbers
for reproducing the work on a larger scale in oil.