top of page

Can KenKen Improve Math Skills?

Updated: Apr 3, 2019

By Tim Walsh

Robert Fuhrer has played in the toy industry practically his entire life. His father held executive positions with toy companies like Matchbox and Topper Toys, and so the younger Fuhrer grew up in toyland.

In 1981, Robert founded Nextoy, a company that connects original toy and game ideas with the companies that market them. Although he cut his teeth with hit games like Crocodile Dentist and Gator Golf, it was a trip to Japan that may have cemented his name in the annals of education. There he discovered a logic and math puzzle known as KenKen.

How did you first discover KenKen puzzles?

An important part of Nextoy’s history is working with Japanese resources. On a trip to Japan in 2007 I met with a longtime Japanese colleague and book publisher who had just begun offering books of this logic and math puzzle called Kashikoku-Naru-Puzzle, which literally means "a puzzle that makes you smarter." Ken means wisdom in Japanese so KenKen means wisdom squared.

The numerical logic puzzle was invented by Japanese mathematics teacher Tetsuya Miyamoto in 2004 to help his students improve their calculation skills, logical thinking and patience. What can you tell us about him?

Miyamoto is one of the most dynamic educators in the world. His philosophy is “the art of teaching without teaching” which emphasizes logical thinking, patience and perseverance rather as opposed to learning by memorization.

Let's Play! Each KenKen puzzle consists of a grid. Your goal is to fill in the entire grid with numbers, making sure no number is repeated in any row or column. So in the 4x4 puzzle at right, you would use the numbers 1 through 4. The outlined areas are called "cages" and the top left corner of each cage has a "target number" and a math operation. The numbers you enter into a cage must combine (in any order) to produce the target number using the math operation noted. Scroll to the bottom of this post so see the solution to this puzzle!

How did 30,000 teachers come to use KenKen puzzles to improve math and problem solving skills?

KenKen’s pedigree began in the classroom, but to get a larger audience we followed the sudoku method of publishing KenKen in major publications such as Readers Digest and the New York Times. We’ve also had wonderful support by numerous educators and organizations such as the National Council of Teachers of Mathematics and Discovery Education.

Tell us about KenKen Classroom.

We quickly noted strong interest from educators, so we started the KenKen Classroom (KKCR) program which supplies teachers and their students with free weekly KenKen puzzles and brainteasers. Teachers can enroll for free at

On your website you call KenKen “Puzzles That Make You Smarter” Do you have any studies that verify this?

This is largely anecdotal, although some teachers have written papers on their experience. We also survey members of the KKCR annually and the reports indicate enthusiastic support of this claim. We would welcome and cooperate with an organization that wanted to explore this more deeply.

Tell us about your tournaments and the International Championship. We began what is now referred to as the KKIC (KenKen Int’l Championship) in 2010 as a small local event. It grows each year and is now hosted by Will Shortz and sponsored by the New York Times. There are five groups which includes 3 student divisions by age, and adult and senior divisions. KenKen is rare in that our events have entrants from the age of 7 to ones in their 80’s!

What’s next in the world of KenKen?

There is a lot happening, especially on the international front. The first major tournament in China will be in Beijing at the end of July. The organization behind it is the same that introduced sudoku to China 15 years ago where it has become a craze. KenKen is also bursting in the UAE as the Ministry of Education endorsed it. It is available on all platforms both digital and analog. 200 newspapers carry it, and there are over 60 books available. There’s the KenKen app on iOS, Android and Kindle.

As promised, here's the solved puzzle from above!

Find out more at:

375 views0 comments


bottom of page