I used an inexpensive canvas, painted the background, broke the crayons and scattered then baked at a low temp until they started to melt. While the crayons were still hot, I used a toothpick to swirl the paint :) FUN!
Glue crayons to a piece of cardboard or to the a canvas. Then get a blow dryer, turn it on, and hold at an angle. The crayon will start to melt and drip in the direction of the hot air. Put cardboard behind the art piece, the crayon will splatter.
Shave crayons in whatever color/pattern onto a canvas, cover with wax paper and iron the whole canvas! The crayons will melt, creating your masterpiece! I've melted shave crayons between two pieces of wax paper before but I love this canvas idea