A paper-roll core that is a soluble, disposable carrier for cleaning and/or disinfecting chemicals. The paper-roll cores are toilet paper roll cores and paper towel roll cores and are rapidly soluble in water and may release cleansers, disinfectants, colors, etc., upon dissolving. Described are: methods of using, manufacturing, advertising, and distributing the paper-roll cores; and methods of advertising and distributing such paper-roll cores to children, who will particularly enjoy the novelty; and methods of modifying existing paper-roll core manufacturing equipment to manufacture soluble cleanser-dispensing paper-roll cores.