Last year the art teacher at my daughter's school requested that we save plastic bottle caps. After collecting for awhile the middle school children began an art project using paint, plywood, screws and bottle caps.
They started by painting the back of the elementary school to look like a field. Green for grass below and blue above to represent the sky.
Plywood was cut out in the shapes of flowers and insects, then painted using exterior paint.
Using screws the bottle caps were applied over the surface of the plywood shapes, taking advantage of both the color and texture of the caps.
Now what was a plain walkway between buildings is filled with color. The children had a great time and now they enjoy their artwork every day.