"Am I hip?" I asked my wife the other day.

"Heavens no," she said. "And the proof is that no one uses that expression anymore."

That really scared me because I'm depending on some hipness to carry me through the day of Thursday, May 15. That's when I return to teach at the high school in New York where I taught from 1969-1978. It is also the very place I graduated from in 1965. That first year of teaching, my colleagues called me Mr. Kotter, a reference to the old TV series Welcome Back, Kotter, where the main character returns to his alma mater to join the faculty. I took this as a compliment, although it was pointed out to me that as a student, I was more like Horshack, one of the teenagers in the sitcom classroom with a very annoying laugh.

I will have students next month who were not alive in 1970. Wait a second-I will have students whose parents weren't alive in 1970. No, that's not possible, is it? Let me do the math. I shouldn't be torturing myself like this.

Why am I headed back to the classroom for a single day? When I retired 35 years ago, I had not taught long enough to be vested in the pension plan. But recently a new law reduced the number of years required to be eligible for benefits. It was my wife who urged me to check into this after all this time. This is really hard to say, but she was...she was RIGHT. Oh, that hurts.

To receive my back pension, I have to rejoin the New York State Retired Teachers' Association, which requires one more day of teaching in order to be reinstated. I have filled out dozens of forms, signed a sworn allegiance to the United States Government and gone through a background check. They wanted to be sure I hadn't done anything bad in the last 35 years. Fortunately, writing and news reporting do not count.

I also had to get a character reference, so I called one of my first students who always said I was his favorite teacher. "Reuben, I'm going back to New Rochelle High School to teach for a day. You probably think I'm a little old to be doing this again."

"You're not too old, and you'll do a great job in the classroom. I'd bet my first Social Security check on it-the one I got in the mail yesterday."

I emailed one of the teachers I worked with in 1978. Paula, who is still teaching there, advised me that things have changed a lot. "We introduce all the new technology. We use laptops, iPads, global positioning devices, smart boards, and interactive learning touchscreens. Students are fascinated with anything new."

"Great! They'll love my floppy discs and overhead projector."

I'm still not sure what I am going to teach, but I'd love to discuss what was going on back in the era of Watergate, Vietnam, Roe v. Wade, and Kent State. (I wonder if they teach ancient history at the high school level.)

In the '70s gas prices were soaring, veterans were returning from a war that many people thought was a mistake, the federal government bailed out Chrysler and there was unrest in Iran. Come to think of it, I know exactly what to talk about.