SF has always been a great place to be a kid, and it...

It was one of those clear days in early winter, on an afternoon ferryboat to Sausalito. A little boy, maybe 2 or 3 years old, sat with his mother on an outdoor bench near the stern.

His mother spoke to him, but he ignored her. Instead he stared with amazement at a deckhand, who was throwing off the dock lines just before the boat backed away from San Francisco. The deckhand saw the boy watching him.

“Hi, son,” he said. The little boy clapped his hands in delight, as if he had been greeted by some famous celebrity. In the world of children, even ordinary things are amazing.

That boy reminded me of myself, in the long ago days when I thought a ride on a streetcar was exciting, and a ride on a ferryboat was an exotic adventure. Watching the little boy on the ferry made me think again that it must be wonderful to be a kid in San Francisco. Even now. Especially now.

Tom Sawyer, America’s most famous boy, had a Missouri childhood with the Mississippi, caves, steamboats. But a San Francisco kid has a bay, an ocean, a park almost as big as Rhode Island, a lake where you can row boats and feed the ducks. And girls and boys who grow up here have San Francisco.

Those of us who grew up in San Francisco remember what it was like. We could run free on the hills, play one foot off the gutter in the streets, roar down the hills in a homemade coaster, wade in the ocean, fly kites in the springtime. That’s what boys did. Girls did other things and whispered among themselves. When I was a boy, I never understood girls. Still don’t.

Of course, all of our adventures were regarded with suspicion by adults. Now we have turned into our own parents, wary of youth and change.

We will be sure to note that not everything is better in these high-tech days. We could run free and sneak into forbidden places, like construction sites, and railroad tunnels and hideouts. That’s impossible now: kids all have phones and can be tracked down. There’s no escape.

And there are fewer secrets to explore. In the good old days, when we were 8 or 9, many places were guarded by watchmen, old, slow guys who could never catch kids. Now they have security guards, alert for terrorists posing as children.

However, the rest of the world has opened up and there are more opportunities open to kids in the city.

The old San Francisco waterfront used to be a dangerous place — working piers were off limits. And there was usually some nasty labor dispute, tough guys battling each other. No place for kids. Now everybody can roam the whole waterfront, go out on a pier to fish, or look at the seals, or just explore.

And there are easier ways to get around. We all had bikes when we were kids, but there were no bike lanes then, and nobody wore helmets. Bikes are much better now, not those clunky things we rode.

Our horizons were narrower. Most little kids in the city had never seen snow. Family vacations were spent during the summer, at the Russian River or Lake Tahoe, and it took all day to get there.

The city has changed, no doubt about that, but some of the changes are good, especially for kids. There are fewer vacant lots, but places like the Starr King Open Space, a grassland on Potrero Hill. Or the formerly undeveloped Bernal Heights Park, which is full of kids and dogs these days.

I think the world of kids was narrower years ago. We were conformist and had the prejudices of the times. Young people who were different were hounded mercilessly.

The city was smaller, and everybody seemed to know everybody else. In the haze of nostalgia, that seemed to be a good thing. But maybe it wasn’t. San Francisco is much more diverse now, and much more understanding of other people and lives.

And now we come to the greatest mystery of all: How kids who grew up with the Internet are able to navigate a world we never knew.

San Franciscans of a certain age grew up with Miss Nancy on Romper Room or Mayor Art on KRON. Now, a 2-year-old of my acquaintance has her own tablet and picks and chooses which entertainment she wants to watch.

At a family gathering about five years ago, I noticed the youngest guest off in the corner with his phone.

“What are you doing?” I asked.

“Playing games,” he said.

Curious, I asked him about games on a smartphone. “You want a game?” he said. “Give me your phone.”

I did, and in a few minutes of flying thumbs and clicks, he handed it back, with a game installed, a game so simple and clever that even I could play it. I had no idea how he did it. He was 4 years old at the time.

This boy is growing up in a city that is a capital of high-tech, an industry that changed the world.

And better yet, a city that is still a wonderful place to be a kid.

Carl Nolte is a San Francisco Chronicle columnist. His column appears every Sunday. Email: cnolte@sfchronicle.com Twitter: @carlnoltesf