The Missouri State Fair has represented the best of Missouri's agriculture and industry since its commencement in 1901. Developed during the Progressive Era, a time of social reform, its early exhibits reflected an interest in scientific agriculture as a means of improving rural life. School exhibits highlighted new attitudes about teaching. In 1921, Missouri celebrated its centennial at the state fair. Throughout the 1920s and 1930s, the fair encouraged good nutrition and medical care through its healthy baby contests. During World Wars I and II, it promoted patriotism with parades of military recruits. The grounds, originally 160 acres with 19 buildings, are now 396 acres with 124 buildings reflecting changing architectural styles.