Everyone looked swell at South Shore High School’s 50th reunion held last weekend nowhere near South Shore High School.

Some 75 of us trooped to Gino’s East, just off North Michigan, and talked about what you would expect: Donald Trump and hip replacements.

The deep dish pizza — Chicago’s idea of health food — was very good. When we were students at South Shore, on weekends we would drive downtown to get it. (Though Due’s was our fitness center of choice.)

OPINION

We would drive up Lake Shore Drive, one car abreast in each lane, so nobody behind us could get around us. Then we would drive slower and slower until everybody was forced to creep at 5 miles per hour. They would honk and shout foul things at us.

Laugh, I thought I’d die. And if you think that was fun (and you probably don’t), there was mooning.

Mooning was when a passenger would stick his bare butt out of the window. If all four windows were filled with bare butts, it was called a Star Cluster. (Do not try this at home. We were experts.)

Forgive me if I wallow in memories that are a half-century old. John Banville, whom I consider one of the greatest writers in the English language, once wrote: “The past beats inside me like a second heart.”

The past beats like second hearts inside all of us who went to South Shore. And that’s because all we have is the past. Our South Shore is gone. Discussing it is fraught with controversy. When we went to South Shore High, it was overwhelmingly white and solidly middle class.

Today, South Shore is overwhelmingly black and economically struggling.

I took the statistics of South Shore’s ZIP code, which pretty much match up with the entire South Shore neighborhood, and found this:

The median household income in America is $51,939 a year. In South Shore it is $26,797.

The unemployment rate in America is 4.3 percent. In South Shore it is 21.3 percent.

The poverty rate in America is 13.5 percent. In South Shore it is 33.8 percent.

This creates problems we didn’t imagine when I went to high school. In the South Shore High of 1966 there were a few really wealthy kids, a few kids from families that were pretty close to working poor, and most kids in the middle.

But I didn’t know any kids who were homeless.

Today, there are homeless kids not only at South Shore, but throughout the school system. The numbers are in dispute. In the 2013-2014 school year, the public school system said the number of homeless kids was 5 percent of school enrollment.

That sounds pretty low. (And one teachers union exec told me the rate at South Shore was 20-25 percent.) But if the 5 percent rate is the same today, that would mean more than 19,000 public school students in Chicago are homeless.

Some are living “doubled-up in the homes of others, often in overcrowded and tenuous conditions,” according to the Chicago Coalition for the Homeless. Others live in shelters. But when I checked the Chicago Public Schools website, it said some homeless school kids lived “in cars, parks, public spaces, abandoned buildings, substandard housing, bus or train stations or similar settings.”

Public spaces? Does that mean homeless kids go down to Millennium Park at night and sleep under the Bean?

Why are there any homeless kids? Why couldn’t Chicago just open the schools at night and let the homeless kids sleep there?

Nah, makes too much sense.

I gave a speech at the reunion — the most dangerous place in America is between me and a microphone — and what happened after I talked about homelessness in the school system?

Did the alums keep chomping their pizza and swilling their beers? Well, yes. But some of them also, on the spot, formed an ad hoc committee to investigate homelessness in South Shore schools and see what can be done about it.

We may not be the Greatest Generation, but the Children of the Sixties did more than do drugs and each other.

Today, we would be called bleeding hearts. But that’s better than having no heart at all.

Some of us have retired or are planning to, and naturally we are trying to decide whether we have achieved anything in the years since we graduated.

I say we should be easy on ourselves. In the words of Woody Allen: “I don’t want to achieve immortality through my work, I want to achieve it through not dying.”

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