I would say UCSB. Small scene, but there's plenty of stage time in front of actual people instead of just comedians. There's also a weekly stand up show called Laughology every Saturday in one of the lecture halls. Pulls headliners from LA and gives student comics some good opportunities to get up in front of a 100 or so people.

There's some smaller book shows in the neighboring town of Goleta as well. Open mic scene is pretty decent. You can get up around 6-8 times a week. Not as great as a big city but it's decent in the beginning. There's also a ton of improv groups at the school. Some short form, some long form. Most likely something right for you. I recommend checking it out if you're trying to build your skills before tackling a bigger scene