Most math grad students are supported as Teaching Assistants. A first-year Teaching Assistant usually spends five hours per week (on Tuesdays and Thursdays) conducting quiz sections for calculus or pre-calculus courses that meet with a faculty member on other days. Teaching Assistants also hold office hours and share in the grading of exams. The duties are not too heavy and are scheduled so as not to conflict with one's graduate study. New TAs are given extensive TA Training, and have many resources available throughout their appointment to help them improve their teaching skills. After the first year, there are a variety of assignments available to TAs, including

Beginning TAs receive a base salary ($1,525 per month in 2011–2012); see the University's Graduate Student Service Appointment Salary Schedule for current salaries), plus a waiver of tuition (except for approximately $350 per quarter in required fees). After completing of a full year of graduate study at UW and making normal progress, TAs will be promoted to the rank of Predoctoral Teaching Assistant I (PDTA I), which carries a somewhat higher salary, and students who teach their own sections of courses are usually paid at the level of Predoctoral Teaching Associate II or higher.  (See the Guidelines for TA and RA Appointments for details.)  There is usually an increase in the salary schedule each year.

Most new PhD students will be given supplementary awards or fellowships in addition to their base TA salaries. These awards bring the annual stipend up to at least $20,000 (and, in some cases, significantly higher) for each of the first five years.

To be considered for a Teaching Assistantship, applicants should indicate in the appropriate place on the Math Department Application for Admission and Financial Aid that they wish to be considered for financial support.  TA appointments are made on the basis of the student's potential for successful graduate work, with attention to the likelihood that the applicant will perform the TA duties in a satisfactory manner. Continuation of the appointment from one year to the next is based on the student's performance as a graduate student and as a teaching assistant. It is unusual for an appointee to find it difficult to handle these duties properly.

The number of new TAs appointed varies each year, but in recent years there have been around 20 TA positions available. All new TAs must participate in the Mathematics Department's TA training program, which is held in September before the start of Autumn Quarter.