Idaho Code § 18-3308

No person, firm, association or corporation shall sell or give to any minor under the age of sixteen (16) years any powder, commonly called gunpowder, of any description, or any dynamite or other explosive, or any shells or fixed ammunition of any kind, except shells loaded for use in shotguns and for use in rifles of twenty-two (22) caliber or smaller, or any firearms of any description, without the written consent of the parents or guardian of such minor first had and obtained. Any person, firm, association or corporation violating any of the provisions of this section shall be deemed guilty of a misdemeanor.