Colorado Academy mourns the loss of beloved CA mathematics teacher and former mathematics department chair, John Threlkeld. Threlkeld passed away June 7, 2015.  His death comes after decades of battling diseases of the blood that eventually necessitated a bone marrow transplant. John was hospitalized a year ago to begin transplant procedures, and eventually, he lost what began as a very optimistic but tough fight for his life.

 

There could be no person more deserving of length of days; no teacher more gifted, no human more gentle, patient, or forgiving. Never did he cast judgment or doubt; he only looked up and ahead. Never did he lose faith in the ability of a student to grow, learn, change, or achieve.

 

Threlkeld spent a good part of his career  -- from 1986 to 2008 -- at Graland Country Day School in Denver teaching mathematics, and in his own words, “after writing recommendations for future CA students for a couple of decades while teaching Middle School students, I decided to teach high school math to see my former students in action.” He joined the Colorado Academy faculty in 2009. 

An alumnus of both Graland and Colorado Academy, Aaron Goldhamer wrote of Threlkeld, "The digits of Pi extend infinitely.  So does your impact on this world, in ways you may never know.  Thank you for being an exceptionally positive impact on my life."

 

Threlkeld’s passion for math centered on helping students develop their critical thinking and problem-solving skills, and on using technology to enhance the math experience. He was an expert at Geometer’s Sketchpad and took a sabbatical to develop scores of lessons using this software tool to enhance the teaching of Geometry. Both at Colorado Academy and at Graland, he chaired the schools’ Mathematics Departments, but he was much more than that.

CA Upper School Principal Dr. Jon Vogels says, "From the first time I met John I was absolutely astonished by the range and depth of his intellect.  Not only could he talk math with the best of them, but he was as well versed in current events and educational trends as anyone I have ever met.  Long before it was fashionable, he was an innovative teacher, consistently asking his colleagues, why should we necessarily do what we have always done?  He incorporated all kinds of technology seamlessly into his classroom and was always interested in the next aspect of technological advance."

At Graland, he also served as assistant Head of the Upper School, as Leader of a Math/Science Cohort, as Co-Chair of the school’s Education Committee, as Ninth Grade Dean and as Director of Communications. At CA, he was Math Department Chair, a valued member of the Admissions Committee, and he was instrumental in designing innovative teaching strategies, integrating technology, and creating hands-on learning projects for students.

 

Throughout his career, he taught Geometry, Pre-Algebra, Algebra I, Algebra II, Introduction to Computers, and more. John served the world of mathematics education far beyond Colorado. He was part of educational committees for the National Center for Education Statistics in Mathematics Assessment and the National Assessment of Educational Programs. As a member of the standing committee on mathematics for the Educational Records Bureau, he helped to author ERB standardized math assessments.

 

He was a presenter countless times at the National Council of Teachers of Mathematics (NCTM), the Colorado Council of Teachers of Mathematics (CCTM), the Technology in Education (TIE) Conferences, the Association of Colorado Independent Schools (ACIS), and many more. His topics ranged from “Mathematics and Music,” “Symmetry and the Arts,” to “What are Pantographs?” or “How to use Good Problems to Motivate Mathematics.”  His teaching practice was examined in detail in the book, Intellectual Character: What it Is, Why it Matters, and How to Get It. [Jossey-Bass, 2002].

 

John was honored as Mathematics Teacher of the Year by the CCTM (1994), by Phillips Exeter Academy as a leading math educator (2009), and by Colorado Academy with the Frances Newton Award for excellence in teaching in 2012.

 

His enthusiasm for his subject transferred to his students.  Threlkeld ran the MathCounts clubs at both CA and Graland – serving as math coach and meeting with students each week for enrichment, practice, and discussion. He especially enjoyed this, as these were students who relished math in the same way that he did; Threlkeld once shared that on his extensive commute to and from Evergreen, all he would do is to excitedly ponder topics in mathematics. The beauty and ubiquity of numbers was always present for him.

 

Threlkeld graduated cum laude in 1976 from Cornell University with a Bachelor of Arts degree in Mathematics and with distinction in all subjects. He earned a Master’s degree from Dartmouth College.  Even while still in college, Threlkeld worked as a mathematics teacher at Verona High School in Verona, New Jersey. He went on to teach math, physics, and outdoor education at schools on the East Coast. Barely out of graduate school, he became the publisher and general manager of the Johnson County News in Cleburne, Texas and comptroller of the family-owned Information Company, the parent company of the Johnson County News. 

 

Threlkeld was preceded in death by his twin brother, Tom Steiner-Threlkeld, and his parents Aubrey and Elizabeth Morgan Threlkeld. He is survived by his daughter and son, Liz Threlkeld (Casey) of Seattle, and Chris Threlkeld (Alex) of Greeley, CO; his wife, Cindy, of Evergreen. CO; and his sister, Laura Threlkeld Anello of Rockaway, NJ. He is also survived by many, many friends, all part of John’s “dream team” of friends and caregivers who visited him in the hospital over the past year.

 

Arrangements are pending. Click here to post a message: CaringBridge.