Elmer's Glue on Canvas, then paint the whole thing. I have totally done this, but with a hot glue gun. Elmer's Glue seems to be a better idea since hot glue leaves behind strings and is harder to work with.
Did you know if you draw on a lightbulb, that the design will cast on your wall at night. How adorable for a child's room -- Even let child design their own lightbulb and watch their art project on the wall!