We have several GTA positions available for the next academic year. The requirements are "good academic standing" (no recent C's or F's; overall GPA of 3.0 or better) and minimum TOEFL score (if applicable).
The main aspects of the Teaching Assistantship (GTA) position are:
1) You cannot have another full or part-time job.
2) Pays $6K stipend each semester.
3) Time commitment of maximum 20 hrs/week.
4) Small tuition grant. (I don't know exactly how much this will be. It should be at least $200 per credit, up to 6 credits per semester.)
5) No healthcare benefits.
Graders work by the hour ($15/hour).
If you need more details to consider either the GTA or grader position, please let me know.