Math is one of Ben Mayo’s favorite subjects. He teaches math at Yakima Valley College, has written two math books that he uses in class and likes working through math problems with his students.

But it’s not all about numbers for Mayo, who along with his degree in math education from Central Washington University also earned a degree in music from Whitworth University with a minor in religion. And he’s written two other books, neither of which have anything to do with math.

Those books — “What’s the Difference Between ...? Vol. 1” and “What’s the Difference Between ...? Vol. 2” — are self-published collections of twisted phrases leading to bad puns, the book covers note.

We’re talking eye-rolling, groan-inducing bad puns. Such as:

• What’s the difference between an animated film and an auto mechanic? One tunes cars and the other is a cartoon.

• What’s the difference between a very fast sailing vessel of the 1800s and an online barber supply site? One is a clipper ship and the other ships clippers.

• What’s the difference between the Rolling Stones and a piece of asbestos? One is a rock band and the other is a banned rock.

• What’s the difference between the state that is north of Oregon and 2,000 pounds of dirty laundry? One is Washington and the other is a ton of washing.

Mayo recently highlighted his latest literary effort showcasing what he likes to call his “twisted humor” during a book signing at Encore Books in downtown Yakima. He brought out some of his best (worst?) puns, sold 32 books and reconnected with friends and former co-workers.

Mayo is the only instructor who writes his own textbooks that are sold in the campus bookstore. His equally unique teaching style reflects his laid-back approach to a subject that can cause plenty of groans on its own.

“I like to think of myself as more of a coach than an instructor. I think more in terms of getting down in the trenches .... it’s not a ‘me against you’ kind of thing,” said Mayo, who wore jeans and a sweatshirt to a recent Math 50 class in the Glenn Anthon building.

Students appreciate his whimsical approach.

“He makes it fun and simple to understand,” said Elizabeth Quiroz.

Born in Yakima, Mayo grew up in the Wenas Valley. The family sold its ranch and Mayo returned to Wenas as an adult after marrying wife Sue in 1982, but between those moves he spent some time traveling inside and outside the United States.

“In 1976, when I would have been in eighth grade, I skipped eighth grade and spent it in Nigeria,” said Mayo, 59, the father of two adult children. “My dad was a civil engineer and Nigeria had a civil war. ... When it was over, (countries) dumped money in the form of aid and my dad went as part of that. He was doing enginering, road construction, that kind of thing.”

Mayo spent ninth grade in a boarding school in Utah while his parents remained in Africa. Everyone returned to Yakima the next year, and he later graduated from Eisenhower High School.

He then spent a year touring with a Christian rock band known as Heirborn (check it out on YouTube).

“I came back off the road with the band and started back at YVC; I decided to do engineering. And then somewhere in that process, I started tutoring my fellow engineering students in physics and really loved it,” said Mayo, who leads youth worship on Sunday mornings at West Side Church.

“Ultimately I ended up pursing my math education degree.”

His two math books — “Arithmetic With an Introduction to Algebra” and “Prealgebra,” which is in its second edition — started as a few chapters on basic concepts.

“The print shop put that in a booklet form and I got my colleagues to use it to give me feedback. I had to do it in such a way that they could integrate it in a way with a book we were using at the same time,” Mayo said. “It had to flow with book we were using.

“Originally it was four separate booklets, four separate chapters, then it got to a point where the book’s finished; do we as a department want to adopt this book as opposed to the book we are using?”

Every time a publisher issues a new edition of a book, departments choose whether to use the latest edition or go with another book, Mayo said. It’s typically three to five years between editions; the book-writing talk turned serious when it was only one year between editions of a certain textbook.

“If I wrote a book, we wouldn’t have to do this,” he said. “My thought was if I wrote a book, it would be cheaper, and students wouldn’t have to keep buying new books.

“The book we were using was over $100. I think both of my books are between $35 and $40 brand-new,” Mayo said of his books, noting that Heritage University in Toppenish began using them in its high school equivalency program this school year.

Departments vote when deciding on books, so Mayo — who is the math department head — couldn’t participate when his became an option. Instructors gave his prealgebra book a thumbs-up and began using it 10 years ago.

“And then a couple years later, I started working on the arithmetic book,” said Mayo, who mostly teaches algebra — his favorite kind of math.

He stresses that the abstract thinking process involved in algebra will carry over into real-life problem-solving, but not everyone is convinced. Humor helps.

“I tell my students I have a stupid story for everything if it helps them learn something,” he said. “I try and get them to relate to the information.”

In a recent class, Mayo used money as an example of a concept and joked with students about their jackets.

“(He’s) funny,” Alissa Garcia said. “For being the second day of class, everyone’s pretty engaged.”

So that’s the story behind the math teaching career. But what about all those bad puns?

“My family has always been joking. In fact, my mother’s maiden name is Nutley, so I came by it naturally,” Mayo said. “My family has always had that twisted humor; I kind of grew up with that.”

He started writing down his bad puns on paper or typing them into notes on his smartphone about a year ago. “After the first one, my brain wouldn’t shut off, so I kept writing them,” he said.

He recently came up with four while lying in bed, Mayo said. “Sometimes they pop into my head, other times a conversation with someone will spark an idea,” he added.

They start out as a word or a phrase with more than one meaning.

“We just had our floors redone. A friend who is a contractor said the word draft. You’ve got draft horses, draft beer, drafting board,” Mayo said. “I had the word draft. How can I use that?

“Typically you need at least two words. So I thought, OK, you’ve got a draft horse, a strong horse used for pulling stuff, and then you’ve got a draft that’s a cold wind that comes in under your door; you could get a cold, you could get hoarse. So one’s a draft horse, the other is a draft that makes you hoarse.”

Groan. And that’s not all.

“I’m already through about half of the third book,” Mayo said.