Most public school teachers belong to at least one union, which bargains on their behalf with federal, state, and local officials for better wages, benefits, and working conditions. Some larger unions, particularly the National Education Association (NEA), also lobby federal and state lawmakers for pro-education policies and adequate funding. The ability to negotiate through a teachers' union is determined by state law, as some states prohibit the collective bargaining of public employees (including Virginia and North Carolina).
Teachers, as with other public employees, do not have the constitutional right to collectively bargain (that is for the states to decide). But the First Amendment does provide that people have the right to "peaceably assemble," which includes the right to join a union (if not as a vehicle for collective bargaining). Also, teachers do not have the constutional right to go on strike, although that right may be granted through other federal or state laws.
A bargaining unit is a group of professionals who share a "community of interests," typically embodied by a union. A teacher may belong to more than one bargaining unit. While most teachers belong to the NEA, which is the largest bargaining unit in the U.S., they also may belong to a state or local union. The NEA represents the interests of all public school school teachers in the U.S., while a local union may serve as the bargaining unit for a single district.
State laws and the National Labor Relations Act (NLRA) establish the procedures used for the recognition of a formal bargaining unit. After a bargaining unit is organized, members may petition the proper labor board for certification. If the labor board determines that the bargaining unit (or union) is appropriate, then the workers will vote to decide whether the organization becomes their offical bargaining unit.
Unions negotiate on behalf of their members for better compensation, but they also handle grievances; provide training; lobby federal and state lawmakers; and work to improve education quality for the students (such as reducing class sizes and improving curriculum). Unions may collectively bargain on behalf of teachers for a variety of reasons, including (but not limited to) the following:
Teachers who choose not join the union may not have to pay monthly dues, despite reaping the broader gains of the union (such as better pay, etc.), but they may lose other perks. For instance, teachers' unions provide legal protection and advice on a wide range of work-related issues. This may include representation and liability insurance to protect against lawsuits by parents. Additionally, union members often have access to a wide range of support and guidance, including curriculum guides and professional development opportunities.
As many as 18 states require non-union teachers to pay a fee to the union as a condition of employment, with the idea that their pay and benefits are directly related to union activity. These states include California, Illinois, New York, Ohio, and Pennsylvania.
Consider speaking with an education or labor attorney if you have additional questions about teachers' unions and collective bargaining.