How about turning a wall into a blackboard, using blackboard paint ?

Painting services exterior
It is indicated for the protection of surfaces in concrete , exposed brick , some
types of stones and, mainly, wood . It can be colored or colorless. Used
in tiles , plastics and floors , it is waterproof and highly durable. It requires
careful preparation, with the addition of catalysts for its correct finish. Therefore,
the application must be indicated by a specialist. Some paints allow you to
innovate and be creative in decorating . Or, still, lacquering, restoring or
creating a metallic finish on the furniture?
These alternatives are possible, as well as using products with advanced
technology, which help in the thermo-acoustic isolation of spaces. It’s common
for inks to get lighter (or darker) when they dry. Also, the color swatch does not
allow a broad view of the tone in the environment .
Some manufacturers make virtual color tests available on their websites. Even
so, the accuracy can be lacking. So if you want to be sure of the hue, buy a
small gallon and test it on a stretch of wall