It took us months to find time to visit the Maritime Museum. We thought it was just another tourist venue but the vessels on display are rich in history. Even the replicas have interesting back stories. We most enjoyed the Star of India where we spent the most time. A docent checked on us periodically to answer questions and provide intriguing factoids. We used the free Passport to San Diego http://passporttosandiego.com/company/maritime-museum-san-diego coupons to save a few bucks on admission. It was well worth the time to visit - we wish we'd done it earlier.
We took a bay cruise on the Californian Cutter, a Tall Sailing Ship hosted and staffed by volunteers from the Maritime Museum. It was a Blast! I helped host the sails ...but you don't have to. It was an experience I won't soon forget! The staff are all knowledgeable and friendly. It was a great day and I would gladly go again!