One of my fall art projects came from Fall Leaves.
We basically followed Cassie's instructions, except that we created leaf rubbings (using wax crayons and a black paint wash) for the background rather than the ideas that she suggested.
What intrigued me most about the project is the "metallic" leaf created out of cardboard, leaves, tinfoil and spray paint. In the end they really looked as if they were tarnished metal.
If I were to do it again, I would perhaps have each student create several "metal" leaves for their background.
As you'll notice, some of the backgrounds are more grey than black - I made them with different classes and added more water to the black paint.