Fourth grade created their own scratch boards by coloring very hard with crayons on tag board. Then they covered their designs with black paint (plus a little dish soap) to create the surface. They learned all about visual textures like stippling, scumbling, hatching, and cross-hatching, and applied those to their animals. They learned how to break the animals into basic shapes in order to draw them. We used semi-transparent paper to help trace the basic shapes, but all of the textures and details were drawn from observation. We transferred our sketches to our scratch boards with chalk and began scratching away!
Many students' scratch art portraits turned out great. We did have to touch up a few with black paint who went scratch crazy and scratched too much. The ones that didn't work out so well were the ones that weren't colored enough. You have to color REALLY HEAVY to make these work.
Here is some of their work: