“Schoolhouse Rock!” composer Bob Dorough. (Lauren McEwen/For The Washington Post)

If you grew up in the 1970s and ’80s, there’s a good chance you learned at least some of your multiplication tables while you were watching Saturday morning cartoons on ABC. “Schoolhouse Rock!” debuted on television in 1973 as part of an effort to add an educational component to children’s programming.

We recently spoke with Bob Dorough, who wrote all of the show’s multiplication songs —as well as some other favorites including “Conjunction Junction” — about the cartoons and how he turned math facts into something fun. Here are edited excerpts from that conversation.

Math often gets a bad rap. How did you come to write these songs to make it more fun?

I was commissioned. This great man [David McCall] was looking to spend money to find a composer to give him “Multiplication Rock.” He said, “My little boys can’t memorize their multiplication tables, but they can sing along with the rock stars like Jimi Hendrix and remember all of the words to the songs. So why don’t we do that and call it multiplication rock?” It took me two weeks to come up with the first one. I did a little studying and looked in a New Math book. I started gathering all of the threes I could think of: trinities, three’s a crowd, third time’s the charm. . . . The whole thing was pretty much off the wall. When I brought “Three Is a Magic Number” to them, they all jumped up and down and wanted me to write more.

What is your favorite math-related “Schoolhouse Rock!” song?

Naturally, I feel a great affinity for “Three” because it’s more or less what got me to do the whole thing. But I think of “Lucky Seven Sampson” as me. I’m a musician, and I did do some work in my youth, but I’ve been lucky to get to sing and play [as he says this he breaks into song, sounding exactly how I remember him from my cartoon-watching days]: Making people happy, that’s my favorite game/Lucky Seven is my natural name/Slipping and sliding my whole life through/Still I get everything done that I got to do/Because I was born beneath a lucky star.

Did you like math as a child?

It was quite easy for me. My father was a salesman/merchant, and he could quickly add up a column of grocery amounts. He always looked over my shoulder when I did my math work. I only went through algebra and geometry, though. My friend said, “Someday you’ve got to write Calculus Rock,” but I don’t think I’m up to it.

These songs seem to still be popular with kids today. Why?

Teachers loved it, and they have secured the DVD and use it in the classroom quite a bit. I do still play elementary schools, where I do mostly multiplication rock, then I’m a jazz singer and I play in bars. In the ’80s and ’90s, the waiters in the bars were college students, working their way through school, and they would hear me sing and say, “We like your voice, it sounds familiar.” Then pretty soon the waiters were begging me to sing “Schoolhouse Rock!” I’ve come to pretty much work a few of the songs into all of my performances.

And what about three? Why is three a magic number?

Here you have the assignment to write multiplication songs, and somehow it seemed natural to pick something obvious. It started with me coining that line: Three is a magic number. Then I went to some of my esoteric books to find out if three really was a magic number. It turns out it is. It’s one of several. Then I began to think of the trinities, and just gathered them all. Before I went to my piano I had all of this in mind: Past, present and future; faith, hope and charity; heart, brain and body. I went to my piano and began to play it over and over to get it in some kind of sensible, logical shape.