Teacher aides

A teaching assistant (TA) is an individual who assists a professor or teacher with instructional responsibilities. TAs include graduate teaching assistants (GTAs), who are graduate students; undergraduate teaching assistants (UTAs), who are undergraduate students; secondary school TAs, who are either high school students or adults; and elementary school TAs, who are adults (also known as paraprofessionals or teacher's aides). By definition, TAs assist with classes, but many graduate students serve as the sole instructor for one or more classes each semester as a teaching fellow or graduate student instructor  Graduate and adult TAs generally have a fixed salary determined by each contract period (usually a semester or an academic year); however, undergraduates and high school students are sometimes unpaid and receive course credits in return for their assistance.

Graduate Teaching Assistants
Graduate teaching assistants (often referred to as GTAs or simply TAs) are graduate students employed on a temporary contract by a college or university in teaching-related responsibilities. In New Zealand, Australian, and some Canadian universities, graduate TAs are known as tutors. TA responsibilities vary greatly and may include tutoring; holding office hours; grading homework or exams; administering tests or exams; and assisting a professor with a large lecture class by teaching students in recitation, laboratory, or discussion sessions. Graduate TAs should not be confused with teaching fellows (TFs) or graduate student instructors (GSIs), who are graduate students who serve as the primary instructor for a course.

Undergraduate Teaching Assistants
UTAs usually serve as true assistants to a class; they typically have taken the course with which they are assisting, often with the same professor, and have performed well in it. This case is less common for GTAs, since many would have been undergraduates at other institutions. Unlike professors and GTAs, UTAs generally do not have a fixed salary but instead are paid by the hour, earn credit hours, or volunteer their time.

High School Teaching Assistants
The term teaching assistant is used in the high school and middle school setting for students or adults that assist a teacher with one or more classes. The responsibilities, situations, and conditions of these individuals' involvement differ from those in higher education. A less formal position, a TA job in secondary education is generally determined by the supervising teacher. Common tasks include grading tests and papers, assisting students with their work, and taking attendance. Some teaching assistants at this level may teach portions of the class lessons, or teach lessons to small groups of students who need extra instruction. Many TAs work "one-on-one" with special needs students; these TAs shadow their student and assist with classwork, organization, and behavior management. In some parts of the United States it is customary or even required that each classroom have one certified teacher and one or more co-teachers or teaching assistants.

Elementary School Teaching Assistants
An elementary school teaching assistant is an adult who is hired to help a teacher with class-related duties, which are similar to those encountered in middle and high school settings. They are sometimes referred to as paraprofessionals ('paras' for short) or teacher's aides. Elementary school teaching assistants are generally hired on a contract that lasts the entire academic year.