<p>The introductory classes at UCSD is 180 max and the teacher or professor is teaching them, not TA. I called the school and people told me when the session reaches the max another session will be opened. So last year for the introductory data structures class, there were 2 sessions, one had 179 and the other had 135. So check out individual UCs and try to learn more about each UC. Not all UCs are the same. I believe UCSB also has small engineering/CS department. Something like 300 max.</p>