The 1950s: Special Education Reemerged.
The Civil Right to an Equal Education Was Recognized.
In 1904 in Europe, Binet and Simon developed tests to determine if a child "suspected of disabilities" should be transferred to a special education class. The test determined if the child was unable to benefit from regular class instruction. In 1916, Terman standardized the Binet-Simon test for American children. Thus began our history of systematically sorting children into special and regular education. It would take most of the rest of the 20th century to turn that tide around.
The number of special classes grew from 1915 to 1930. With the Great Depression of the 1930s, there was a dramatic decrease. At that point, according to the Arc US, "Mildly retarded children either stayed at home or attended regular classes. The more severely retarded youngsters were placed in institutions."