I happened upon this large black poster board for $.59 cents and an entire box of chalk (which I will reuse later), for $.99 cents
I already had a decent ruler at home which I hot glued) for him to hold it up and voila...
A 'Chalkboard'
It took me 45 minutes to draw on the lettering in a 'somewhat' creative design. (It was all I could muster up).
Tips: spray with aerosol hairspray at a 3 foot distance (test first on a small area) to keep chalk from rubbing off.
T-bone 2 rulers on the back for better structure.
Actually cost me far less than $1.58 because I didn't use up all of the $.99 cent boxed chalk!