While the above linked article has a lot of fun activities, they are listed as being in San Francisco. They are not all in San Francisco, especially the snow day activities. One of the activities is in Santa Cruz, which is over an hour outside of the city limits.
There are a few things on the list that I would really enjoy, such as the Golden Gate Park lights and the Lego exhibit. I would suggest the aquarium in the Academy of Science over the Aquarium at Pier 39. There is just more to see there.
This list is pretty good, but you definitely need to do your research before trying to visit these places. Some of them aren’t what you’d expect. Look up addresses, drive time, and prices before heading out on your journey, but go for it!