To make a scratch-off painting, you will need:
A paper plate or some other thick paper that can handle paint.
Oil pastels or crayons
Black acrylic or tempera paint
A palette (you can make one on anything including paper, foil, plastic cups, an old plate, a piece of cardboard)
A paint brush
A cup of water
Some napkins
A trashcan or waste basket
A toothpick or something to scratch with (a fingernail, piece of card, a comb, spoon, fork, or the other end of your paintbrush)