Is Marina in San Francisco a good place to live for families with kids?

I've got a 4 year old and we're friends with many families who live near us. The two challenges are the expense of the neighborhood - my favorite block the homes we like start at $2 million, and a 2+ bedroom rental starts at $4,000. The other is schools - public schools are hard to get into if you want to choose a top notch one, and the private ones are expensive. But if you like BOTH urban living AND parks and outdoor space, the Marina and San Francisco are amazing. We can walk or bike to the beach (too cold to swim, but tons of fun still), we walk and scooter to two kids playgrounds, and so, so, so much more.