The Exploritorium is a great place to take kids.
So is the Aquarium and one other place I can’t remember the name of.
The rest not so much.
Academy of Science - its got the Aquarium, but has a lot more too.
The SF Zoo is excellent, for a small zoo. It is by far the best in Northern California.
Golden Gate Park is great, a wonderful place to wander and run around. Some homeless troubles but can be avoided.
There are plenty of playgrounds, in the good (and non-hip) neighborhoods quite decent and safe.
The beach is weirdly interesting. Lots of dogs though.
Moscone Center Ice rink is excellent, probably the best in Northern California also.
Sightseeing is a delight. SF is in a beautiful natural location, and the legacy of late 19th-early 20th century architecture is still there and in fine shape generally. Its a great city for kids to bike on the sidewalks over most of the city.
Public libraries - Very good availability. Easier to get to, more of them than is usual in most suburbs here.
Organized sports - Plenty ! People over-schedule kids into these things actually. Its easy to find and get kids into Little League, or pretty much anything else, even hockey.
Lacks -
- Organized child-centered entertainment. Lack of things like mini-golf, go-karts, water parks, etc. You have to go out of town for these. For the most part the lack is due to the lack of and expense of land, but also the limited clientele, there being few kids.
- Outdoor swimming pools - this is mainly due to the weather. There is no real summer here. There are quite a few accessible indoor pools but they tend to be over-organized, oriented mainly for swimming lessons and competition swimming.
- Toy stores - There are just a few small ones.