Great thing to do on a beautiful, sunny day: cardboard sliding

The semi-ancient sport of cardboard sliding down a grassy hill. Or cardboard tobogganing, as some purists might call it.

Ever do that as a kid around here? My son and I just got back from a walk around our neighborhood. He has the day off from school, me from work, because of the Martin Luther King Jr. holiday.

Our walk included a stop at his elementary school playground. His school is built against a steep hill that, ever since I was a kid, growing up in this neighborhood, was well known in the neighborhood, and even around Walnut Creek, as a primo spot for cardboard sliding.

My older brother used to bring me to this hill to do this. On visits to Walnut Creek with his sons, now all teenagers, he's brought them back to the hill to cardboard slide.

This afternoon, my son was scootering around the playground, then we sat on the swings and talked. We noticed three middle-school-aged boys ride by us on their bikes and toward the hill. One boy was holding huge, long pieces of cardboard. These boys came well prepared.

A few minutes later they had climbed to a particularly steep part of the hill, with a slope of more than 45 degrees. One by one, they seated themselves on the cardboard at a level spot on the hill just below an oak tree. They then launched themselves, like Olympic tobogganers, off that platform and down the slope.

It was fun to watch, and I thought of doing this with my brother when we were kids. He would say, though, that the moist green winter grass around here does not offer optimal sliding conditions. You need to wait for summer, when the grass is yellow, bone-dry and as slick as ice. It's in those conditions that you get real, heart-pounding speed down the hill.

Still, these three boys got some speed going. One crashed and took a roll, once, twice. He stood, brushed himself off ,and headed back up the hill for another slide.

As a parent, I see potential broken bones. But in trying to remember doing that as a kid, I could remember pure, thrilling, free-falling joy.