This lesson is definitely one of my biggest hits (I'll have to come out with a 'Best of Mrs. Nguyen' blog post one day)! :) Fourth graders began by reviewing what they already knew about value (the element of art). Afterwards they began working on their art projects. To begin students glued down a piece of olive green yarn to a 12"x18" piece of black paper. The only stipulations I gave them was that it should start from the left end of the paper, reach all the way to the right end, and…