Go all the way to the Bay end of Pier 39.
The Sea Lion Cafe is on the 2nd level,
Left hand side.
If you travel to Pier 39 in San Francisco, and I suggest you do, your kids will find the sea lions that have made a home there to be extremely fascinating. Even children who have seen the sea lions in their natural habitat will be thrilled and you will spend a lot of time sitting there in the crowd of other tourists watching them flop about and trumpet at each other, unless you decide to do what we did. We went to Sea Lion Café on the second story of Pier 39 and ate lunch. The dining area of the restaurant is lined with big windows that look out on the bay and down on the sea lions below. We were able to have a tasty lunch, for a reasonable price, and watch the sea lions playing at the same time, and without the distinctive odor. I heartily recommend this as an alternative to the much more expensive restaurants on the pier and as a kid-friendly choice.