For most students, taking time out of their day to do math puzzles seems like a chore. For junior Ellie Grueskin, math puzzles called KenKen are a welcomed and sought out challenge.

KenKens are gridded puzzles that come in 3×3, 4×4, 5×5, and 6×6 varieties. They involve the player filling out cages — smaller boxes within the grid — with numbers that add, subtract, multiply, or divide to the number denoted at the top of the cage. The operation with which the player uses is also denoted at the top of the cage, next to the goal number.

Ellie’s passion for KenKen was fostered at a young age. “My dad was an avid fan of the crossword puzzle in The New York Times and I would always sit with my him while he was doing it on Sunday mornings. One day, when I was about nine or ten, he noticed that there was a little math puzzle on the lower right hand corner and thought it might be interesting for me to try,” she said.

Ellie continued to do KenKen puzzles for fun and as a way to further her arithmetic skills.

In March of her freshman year, Ellie saw an advertisement for a Pi Day KenKen competition in Princeton, New Jersey. In addition to the competition, the inventor of KenKen, Tetsuya Miyamoto was speaking to the participants about how he created KenKen and his philosophy on effective ways to teach math.

Ellie completed the competition successfully and attracted the attention of the president and a few employees of the KenKen company. They asked her to stop by the headquarters in Pleasantville and later offered her a summer internship there.

As an intern, Ellie was in charge of compiling educational math packets and writing weekly newsletters that would go out during the school year. She also coordinated KenKen competitions at local schools.

This past summer, Ellie returned to KenKen headquarters as an employee, helping to create the website for the international championship that took place in December. She also helped set up and participated in talks given by the KenKen company, including one at the Google office in downtown New York City.

In addition, Ellie worked with Hackley’s own Hudson Scholars program, teaching the students strategies for solving math as well as KenKen puzzles.

“Hudson Scholars was extremely rewarding in the classroom as I was able to gain experience teaching math and work with a great group of students…I’d say my favorite part of the program was getting to see how the Hackley community (teachers and students included) could use the insight and experience they’d gained through their time here to educate and inspire others,” she said.

History teacher and advisor to the Hudson Scholars, David Sykes said, “Ellie was incredible with the Hudson Scholars! She came every afternoon with a huge smile on her face, great enthusiasm, and a passion for math and KenKens that was contagious. The combination of her math skills and her ability to connect with the Scholars made Ellie an indispensable part of the two-week enrichment program and a favorite volunteer among the Scholars.”

Ellie’s work culminated in the publication of a book, KenKen For Beginners: Tried and True Tips & Techniques for Beginners, which she co-authored with Joshua Rosen, an elementary school teacher from Dobbs Ferry who uses KenKens to teach math. The book is also available in Hackley’s library. “It’s meant for people who have never seen a KenKen before, or just want to get better at them,” she said. “I like that [KenKen] is a way to apply math outside of the classroom. I think it helps me think in more creative, logical ways because it helps me see that there are multiple ways to solve a problem,” Ellie added.