More than 26,000 union teachers and support staff walked off of the job in Chicago this September, arguing with the city over compensation, benefits and job security.
Teachers and school administrators, both public and private, make up one of the largest unionized blocs in the United States. The National Education Association is the largest labor union in the country, and about 3.1 million, or 37% of all education workers are union members.
Typically, the union members earn $224 a week more than non-union educators, with median weekly earnings at $1,038.
The American Federation of Teachers was behind the Chicago teachers' strike earlier this year, when teachers asked for higher pay, better job security and changes to a new evaluation system.
Major unions: National Education Association; American Federation of Teachers