"Table Top" ink and white crayon 5 x 3 #Inktober

Today my art project students began exploring value.  I gave them black paper and white crayons, and showed them how to look at a black and white image of a round object, observing the zones of light.  I showed them how to use a white crayon to reproduce the different values from 1 to 4 using various pressure with the crayon, leaving the black paper as the darkest. They produced some very interesting work and are beginning to see. 
I made a couple of sample works.  First I painted a rectangle of india ink, the use only the white crayon  to draw my subject. Below is a simple ball I drew to demonstrate the zones of light. 

This is my 19th entry into the #Inktober challenge.
As always, thank you so much for looking.  Leave a comment if you'd like.