Some of these items appeared in posts elsewhere on this blog; I wanted to collect them in one place and add on.
Steven Strogatz wrote two series of columns for a general audience about mathematics for the New York Times. The only way for me to bypass the NYT paywall may be to provide a link for each column, so here goes:
I. The Elements of Math — From Fish to Infinity, Rock Groups, The Enemy of My Enemy, Division and its Discontents, The Joy of X, Square Dancing, Think Globally, Power Tools, Take it to the Limit, Change We Can Believe In, It Slices, It Dices, Chances Are, Group Think, and The Hilbert Hotel.
Here’s an animation that shows factorizations of natural numbers into primes.
For an introduction to Pascal’s Triangle, try this.
I’ve given versions of my talk, “Ringing Mathematics,” to various audiences. Here are some related videos: The Mathematics of Bell Ringing, Change Ringing in the National Cathedral, and Grandsire Caters at Rochester Cathedral.
The Mathematical Association of America puts out a Minute Math problem every day.
Math Munch is a “weekly digest of the mathematical internet.” Click on the “For Teachers” link to see what motivates the authors.
As always, feel free to let me know of things I could add.