Optical Illusions - grade 5/6

Here's an optical illusion lesson that I did with my grade 5/6 class. I saw this art lesson on the walls of a school when I was voting last year, but I know that it's one that is often done by art teachers. It took me a while to figure it out, so I made some step by steps to make it easier on anyone who wants to try it!

To do the background, just follow the steps to the left. When doing this with a class, I often use terminology like "bumps in" and "bumps out". This is how to do it without the circles. If you want to add in the circles, just do them right after step four, before coloring in your sections in black.

Below are the steps to do the circle (just ignore the grid in the background, I modified these instructions from the how-to I did here):

 Then, they color it in, using a checkerboard style pattern. The parts in grey below should be colored in black. The other sections should be done gradient style using colored pencils.

Hopefully this all makes sense. Here are some of the finished projects!