Do you know what you see when you drive through the neighborhoods of suburban America these days?

Empty driveways.

Empty parks.

Empty yards.

Empty sidewalks.

Do you see what's missing?

The kids — where are they?

It's as if someone blew an air-raid siren. They've vanished.

No one is riding bikes on the sidewalk or playing basketball in the driveway. No one is playing pickup games of football or baseball in yards and empty lots.

Well, you're thinking, they're probably in the house playing Nintendo or PlayStation, if they're not texting friends or chatting on Facebook or their cells or surfing the Net. They'd rather play basketball on Wii than on the driveway.

And experts wonder why kids are fat and out of shape?

But none of this completely explains the empty driveways. More kids are playing sports than ever, but now they're doing so at Nike football camps or the Baseball Academy or a seven-on-seven tournament or in super leagues or in a weight room to prepare for next season, whatever that might be …

All their sports are structured and supervised by adults.

They're learning the proper mechanics for hitting to the opposite field or running a post-corner route or sinking a curl jump shot. The fun and spontaneity are gone. Sandlot ball is dead. Nobody's learning to run a hitch route to the mailbox, or a down-and-out behind the parked Ford. Nobody's playing Wiffle ball with a tree serving as second base.

Kids aren't playing unsupervised, improvised games with their friends as much as they once did.

Kids used to rush home after school, change clothes, wolf a bowl of cereal and run outside to play football in the yard with the other kids. They had the outdoors, friends and unstructured time. Now they're taking batting practice with a swing coach.

Kids were like nature — they abhorred a vacuum. If there was an empty lot in the neighborhood or a field, they filled it with baseball and football games. Short of that, they'd play on the street, between parked cars. If there was a hoop with a wooden backboard on the garage, kids were in the driveway playing ball. They didn't quit until Mom called them to dinner.

I lived in a nearly a dozen states when I was growing up, and it was pretty much always the same in each new neighborhood. We filled our spare time with exercise — we just didn't call it that. They were just ball games. In one neighborhood, we played on a weedy, narrow lot that was framed by woods on one sideline and the street on the other. It was about 25 yards wide and 100 yards long. We ran a vertical pass attack.