Coeducation was THE American education during the early twentieth century.  That soon changed…. The single sex reform movement came forward on the public education in 2002. This movement was a response to the amendment No Child Left Behind (NCLB). This amendment allowed single sex schools to be created to improve the educational outcomes for all students. In 2005, only 4 public schools in the United States offered single gender education. By April 2006, 209 public schools began offering single gendereducation.