"Only Mrs. Zabarelli Knows" is a Wubbulous World of Dr. Seuss song performed in the episode "Mrs. Zabarelli's Holiday Baton".

Annie DeLoo starts off on her "Plinktey-Plink" piano, and everyone in the pageant asks what they should do. As the song continues, they sing, "Mrs. Zabarelli is on her way," hoping that she'll arrive and answer their questions about the pageant.