This study documents the music teaching and learning that took place in the U.S. Navy band program at the Great Lakes Naval Training Station (GLNTS) near Chicago during World War I, led by Lieutenant John Philip Sousa. The following six research questions helped guide this investigation: How did Sousa organize the Navy band program? What were the details of teaching the enlisted bandsmen? What other music experiences were provided? How did the bandsmen's work benefit the Navy and the US government? Which of the military band experiences likely influenced teaching and learning of instrumental music education after the war? What were the benefits for Sousa to volunteer near the end of his career? Findings revealed that more than three thousand bandsmen were taught by Sousa and Navy bandmasters. Bandsmen served in several ways: intact bands were sent to Navy ships to boost sailors' morale; bands served the training regiments; bands toured the nation selling bonds; the GLNTS band program impacted the supply of band teachers after the war; and Sousa's and the militaries' educational and training strategies survive in today's classrooms. The study concludes with a critique of the US government's and Sousa's role in commodifying the bandsmen.