Here is the official policy from the CS Department:
We assign one 50% TA for every 30 students in non-lab courses, and one 50% TA for every 25 students in lab courses. Divide that in half for smaller courses: one 25% TA for every 15 students in non-lab courses, and one 25% TA for every 13 students in lab courses. Classes with enrollments less than 8 do not receive TA support. Only courses with at least 3 units and numbered CS100 and above receive TA support
A classed is called a "lab class" if it is a heavy programming class. This being said, some non heavy programming classes are lab classes also.
If you have TAed a lab class and a non-lab class, and feel that the non-lab class was at least as much work than the lab class, please contact us and we will notify help refine this classification.