Paint an eye onto the canvas and then glue small pieces of crayon underneath it. Melt the crayons with a hair dryer and you'll get an effect like this!it's different from the normal crayon melting stuff.
My own efforts at melted crayon art for our daughter. Board is the normal backing to the picture frame. Painted with white chalk paint. Letter and umbrella blanks cut out of cardboard and the rest is obvious from the pics.