I loved doing this in art class. Art With Mr. E: Line Design w/Shading - Grade Very cool, fun art shading project from Art With Mr. E. he's an elementary art specialist. Try this with your kids (but I think grown ups would enjoy this too).
colored pencil/ shading/ teaching value lesson--Medium blue construction paper background. darker blue for the shadow side and white for the lit side. Students choose colors for accessories and add snowflakes in the sky.
Painting with Watercolors, Glue and Salt. This will be a fun project this summer, just paint the canvas with watercolors. add some kosher sea salt (coarse is better than fine salt) and some glue splotches!
Milk Art A plate Milk Food Coloring Dish Soap Fill the plate with a thin layer of milk. Next, put in drops of food coloring. Then, add a few drops of dish soap into the center of the food coloring, sit back, and watch!
Firework Salt Painting - Busy Mommy Media _ This is such a cool art project for kids! It looks so neat when it is done. I love that it uses stuff I already have on hand. This would be awesome for a rainy day activity!