Recently we visited the Seymour Marine Discovery Center, which is part of the UC Santa Cruz. The center is overlooking the ocean and is surrounded by all kinds of wildlife.
There are very impressive skeletons of both grey and blue whales on display outside.
The articulate docents are available to lead tours, which really enhanced the experience. Part of the tour includes watching dolphins play in large pools.
There are several touch tanks with sea stars and hermit crabs as part of the inside exhibit. Other tanks display colorful abalone, anemones, and large soft sea cucumbers.
Seymour Marine Discovery Center http://seymourcenter.ucsc.edu/about.html