For stretch and explore, I used oil pastel. I cut a small piece of drawing paper and used oil pastel to color the circles. Fir the first and last 4 rows of circles, I colored with complementary colors. The last row circles are the opposite of the first row circles (I switched the colors of inside and outside). I chose oil pastel, because I thought it would work well with my art work and I really liked the texture. I also really liked the blending when its colored.