A teaching assistant in a grade-school or high school setting may work with a particular student or several students. Others teach class sections, assist any students who may need extra help and handle other responsibilities such as grading, as the U.S. Bureau of Labor Statistics mentions.
A teaching assistant in a university setting often teaches classes or discussion sessions, either serving as the sole instructor or working with a professor. A teaching assistant often grades papers or tests as well. Sometimes a professor teaches a course and TAs handle much of the grading, reading and assessing students' work.
Teaching assistants often follow a plan outlined for them, whether they teach in an elementary school or college setting. However, they may determine some of the readings or other assignments they will give students.
Sometimes a university-level TA offers extra study sessions to help students to better understand the course material. An elementary or high school-level TA might offer supplementary support by tutoring students after class.
A teaching assistant must exercise patience and good judgment about how to handle potentially difficult situations. He should try to understand what a student is coping with and truly care about helping that student to overcome her challenges. He should also understand the course material and prepare well for teaching.
Although a university teaching assistant must devote a great deal of time to his own studies, he should take the job seriously and make an effort to be available to answer students' questions and discuss their concerns. Although becoming a TA can be overwhelming, it gives students an opportunity to become better teachers.