A brief list of what's new on Math Lair. This is not a complete list of changes; I don't list minor changes here, just new pages or major overhauls. Sometimes I forget to update the page for major changes either.

**April 27, 2020:**I've added Distribution of Terms and two new Pillow-Problems: 45 and 47.**March 30, 2020:**I've added Aliquot Chains for Numbers 1–1000.**March 24, 2020:**I've added Angle Measurement.**March 22, 2020:**I've created pages on Hypothesis Testing and Parameter Estimation and added chapter 7 of The Search for Truth, and made several miscellaneous changes.**March 20, 2020:**I've created Niven numbers and Numbers 11-20 in Different Languages and made several changes to other pages.**March 18, 2020:**I've created a page about the Wuhan Coronavirus with the eventual idea of demonstrating exponential growth (currently I only have raw numbers). Also created a new baseball cards answers page, correlation is not causation, and pages ondecimals and extrapolation.**January 17, 2015:**I've added a page about Eulerian squares.**January 12, 2015:**I've added a page about adding apples and oranges.**January 11, 2015:**I've added eight pages, including Variables, Parameters, and Constants, Recreational Logic, Riddles, and more. I've also written a new book, 125 Lateral Thinking Puzzles.**November 30, 2014:**I've written a new book, Paradoxes, Fallacies, and Braintwisters.**November 15, 2014:**Win a book! To celebrate the 500th page on Math Lair and the 15th year of the cite, there is a contest running until December 15.**November 13, 2014:**A new milestone has been reached: There are now 500 pages on Math Lair. Pages of interest added recently include a new page of lateral thinking puzzles, a page about stacks of books, problems about Rockets (the candy), some more chapters from A Search for Truth, and more.**May 17, 2014:**I've redesigned this site's home page and the site logo and added a new puzzle: The Two Hourglasses.**May 8, 2014:**I've aded pages on Sprouts and Lie Detection Puzzles.**April 14, 2014:**I've added four pages, including a start on solutions for the second practice test in The Official SAT Study Guide and a page on quadrilaterals. There are now 450 pages on the site.**December 30, 2013:**I've added a new game,*Trading Post*.**December 12, 2013:**I've added several eight new pages: The Spider and the Fly, A Christmas Dinner and Some Knotty Problems (both by Henry E. Dudeney), the clustering illusion, noon and midnight, the doomsday argument, Occam's razor, pre-decimal British currency and coins, and a page on errors in the mathematics section of the SAT.**December 3, 2013:**I've added several pages, including another new page of lateral thinking puzzles, several new pages in the "Test Preparation" section, a page on Pell's equation, one on the law of large numbers, and more.**November 16, 2013:**I've added a new page of lateral thinking puzzles.**November 14, 2013:**I've added a fair bit to probability page and added several pages related to probability, including the principle of indifference, flipping a coin, and Monty Hall problem.**October 7, 2013:**I've added about 20 new pages to the site, including a new test preparation section and some related pages, a few chapters from the book The Search for Truth by Eric Temple Bell, as well as pages on the eight queens puzzle, Russian peasant multiplication, guess my number, a "proof" that you never go to school, problems that make use of the pigeonhole principle, and some new book reviews.**July 26, 2012:**I've created a new look for the site (no more blue background, for the most part) and I've added several pages here and there.**July 15, 2012:**I've added some new puzzles, including Lateral Thinking Puzzles, The Well in the Field, The Disadvantages of Being Absent-minded and How Much Profit?**February 16, 2011:**I've moved this site to a different server.**January 27**Added a page about zero. I've also rearranged parts of the site.^{th}, 2002:**November 26**Added a Sierpinski gasket page and a Positional notation page.^{th}, 2001:**November 19**Added a informal fallacies page.^{th}, 2001:**November 15**Added a logic page.^{th}, 2001:**September/October, 2001:**Oops, haven't updated this page in a while with my changes. Recently though, I've added a Physics bibliography, a page on prime gaps, and one on twin primes.**June 17, 2001:**I've added pages on the three construction problems of antiquity, pi, a chronology of calculating pi, the Fundamental Theorem of Arithmetic, how big is a million? and transcendental numbers, and updated about 20% of the pages in the site.**May 14, 2001:**I've added an in-depth divisibility page and updated several others.**April 25, 2001:**I've noticed that I haven't updated this page in a while. So, I added pages on absolute value and chess, and I've updated several pages.**January 28, 2001:**Added a start at a game theory page.**January 20, 2001:**Added a graphs of functions page.**December 26-28, 2000:**Added an Arabic numerals page, numbers in other languages, Greek metric prefixes, and a page on the new millennium. Also updated numerous pages.**December 14, 2000:**Added a Factorials page.**December 6, 2000:**More updates and added a general number theory page.**November 27, 2000:**Made several updates and added a $1 words page.