Squirt a load of value shaving foam into a bowl and add your choice of poster paints. We taped some wallpaper lining paper onto the hallway wall (the one Daddy had redecorated a week ago!) and let the kids paint with the now coloured shaving foam. While they were at it they went outside and painted the wall in the yard. Its definitley an improvement on the dirty white brickwork and really brightens the place up on a dreary January weekend.