Education was a high priority in the Progressive Era, as American high schools and colleges expanded greatly. For men who were older or were too busy with family responsibilities, night schools were opened, such as the YMCA school in Boston that became Northeastern University. Outside the big cities, private correspondence schools offered a flexible, narrowly focused solution. Large corporations systematized their training programs for new employees. The National Association of Corporation Schools grew from 37 in 1913 to 146 in 1920. Starting in the 1880s, private schools opened across the country which offered specialized technical training to anyone who enrolled, not just the employees of one company. Starting in Milwaukee in 1907, public schools began opening free vocational programs.