Books and Articles

"Hidden Harmonies: The Lives and Times of the Pythagorean Theorem"
by Robert Kaplan and Ellen Kaplan
Buy at Barnes & Noble Online!

Buy at IndieBound!

Bozo Sapiens: Why to Err is Human
by Michael and Ellen Kaplan

"Out of the Labyrinth: Setting Mathematics Free"
by Robert Kaplan and Ellen Kaplan

"Chances Are . . . : Adventures in Probability"
by Ellen Kaplan and Michael Kaplan

"The Art of the Infinite: The Pleasures of Mathematics"
by Robert and Ellen Kaplan

more books...


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Disturbed by the poor quality and low level of math education in the country, three of us began The Math Circle in September 1994...



Our courses are located on the campus of Harvard University. [learn more...]

Photo Archive

Gordon Ritter with masters of hyperbolic geometry

Students ponder cake division dilemmas.

Kids explore real mathematics.

Students find a new proof to a classic problem in combinatorial geometry.

Bob Kaplan poses the question

coming to grips with it


Ellen Kaplan starts to infinity.

Jim Tanton pausing for thought.