This table traces the development of the number of schools, classes, students and teachers at secondary schools, i.e. Realschulen and Gymnasien, from 1911 to 1938. After the end of the First World War, the school system in the Weimar Republic underwent extensive reforms aimed at reducing social differences and unequal opportunities in school education. With the “Weimar School Compromise” in 1919 and the Primary School Act of 1920, a school system consisting of a common four-year elementary school and a subsequent division into a three-tier school system was introduced. Promoted by higher state spending on school education, the number of teachers at secondary schools increased in the 1920s. The number of students also increased initially, but then fell again from the mid-1920s. A decline in the birth rate after the end of the First World War led to an overall decline in student numbers. The Nazi “Law against Overcrowding in German Schools and Universities” of April 25, 1933 also meant that Jewish students were almost completely excluded from the state school system. The National Socialists also restructured secondary schools.