Die Kluge or The Wise Girl is an opera in 12 scenes written by Carl Orff. It premiered in Frankfurt, Germany, on February 20, 1943. Orff referred to this opera as a Märchenoper or fairy tale opera. The composer also wrote the libretto, based on Die Kluge Bauerntochter (The Peasant's Wise Daughter) from the Grimm's Fairy Tales and is often paired with Orff's Der Mond.

Der Mond or The Moon is an opera in one act by Carl Orff based on a Brothers Grimm fairy tale with a libretto by the composer. It was first performed on February 5, 1939 by the Bavarian State Opera in Munich under the direction of Clemens Krauss. The composer describes it not as an opera but as Ein kleines Welttheater or "A little world theatre" and is usually paired with Orff's Die Kluge. These 1956 recordings star Elisabeth Schwarzkopf and Hans Hotter. Wolfgang Sawallisch conducts.