In the Spring 1998, I TAed the AI Core Course. This was an exciting experience. First, we got a dream team of three instructors: Andrew W. Moore, Maneula M. Veloso, and Tom M. Mitchell. Second, we had two separate classes: one for CS students and another for robotics folks. You can see it's not easy to TA such a course, and I guess you won't be surprised if you find out that I got two heads (see the above image)
that semester. However, I certainly learned a lot from the dream team and my students no matter what they called me -- an evil TA or a nice TA.