There a lot of options for whale watching tours. Most people go to Dana Point. There's Aquarium of the Pacific and they have some kind of combo ticket and harbor excursion, which I think varies seasonally. There are also tide pools, some well known ones are Abalone Cove in Palos Verdes and Carrillo State Beach. Again, what you'll see varies seasonally. There are also snorkeling excursions to Catalina if you want to take a whole day.