Notan is the Japanese design principle of light and dark. The Yin and Yang symbol is probably the most recognizable example. Before teaching art, I had never heard of Notan, but thanks to Pinterest and YouTube, I got to learn about it and then got to teach it to my third graders.
For this assignment, students were told they needed to make a variety of lines on their paper. The catch, once their crayon starts making lines, it must not lift off of the paper. The paper must be filled and the lines need to be varied (no loopy loops over and over again). This involves planning.