Analogous-Colored Snowflakes

I read Snowflake Bentley to my first graders.  It's a picture book about a farmer-scientist who studied the delicate beauty of single snowflakes.  He developed a method for photographing snowflakes so that he could share this beauty with the world.
I showed students some of Bentley's images, and then I challenged students to draw six different snowflakes in six circles on a piece of heavy white paper.  Each snowflake had to be unique and have radial symmetry.  Students had to press hard on a white crayon to create their snowflake, because then we painted over the images with watercolor.  I taught students how to blend analogous colors in each circle to create a background for each white snowflake.