be well-rounded…. CELEBRATE   PI  DAY !

What’s pi?   Pi is a number that comes from dividing the distance around a circle (i.e., circumference) by the distance across that circle (i.e., diameter). That ratio is the same number no matter how large the circle is. Even though this relationship has been known for thousands of years, it was only 3 centuries ago (1706) that the 16th lowercase Greek letter π (pi, the first letter of the Greek word perimetrog for “surrounding perimeter”) was introduced.  Pi is an irrational number and so its decimal representation never stops or repeats, but computers have found the first 31 trillion (and counting) decimal places!


What’s “Pi Day”?  We can write March 14 as 3-14, and 3.14 is the beginning of that special number pi. For over 3 decades (thanks to physicist Larry Shaw of San Francisco’s Exploratorium in 1988), math classes, math clubs, and museums from coast to coast have observed each March 14 as PI DAY, a chance to celebrate not just pi, but also the too-often-unsung beauty and connections of all math in our world. By passing House Resolution 224 in 2009, the U.S. House of Representatives enshrined March 14 as “Pi Day” to encourage “schools and educators to observe the day with appropriate activities that teach students about Pi and engage them about the study of mathematics.”  Pi Day 2015 was “Pi Day of the Century” because the date 3/14/15 is the only one this century that contains not just three, but the first five digits of pi!  This “month/day/year” format is used mainly in the US (and Belize), making Pi Day a fairly distinctive American holiday! (And, yes, it’s also Einstein’s birthday.)

Pi day on RADIO: Louie Saenz did a 16-minute interview (incorporating 3 of my pi songs or song excerpts) of me for Pi Day 2019 on regional NPR-station KTEP (88.5 FM),; that same station has done several mid-March airings (since 2005) of my special “Pi Day” edition of the “Desert Diaries” show, which sparked the creation of a “math category” of episodes

Pi Day SONGS: 

I wrote “American Pi(click HERE to hear a 3:53 demo recording and click HERE for a related article with lyric and lesson) to present historical highlights (and mnemonic for the first 6 significant figures) of the number pi, and may be sung to the tune of Don McLean’s 1970s #1 hit “American Pie”. Varying versions have appeared in several books and journals and a rockin’ partial rendition by Calvin Coolidge (a band of then-high schoolers in Cleveland) appears at   On 3/14/15, the National Museum of Mathematics announced my song won its “Pi Day of the Century” song contest, which yielded media coverage (see bottom of this webpage).

• I wrote Circle Song (to the tune of “Twinkle, Twinkle, Little Star”) to help secondary school students recall –and distinguish-- the two most common formulas associated with circles.  Click HERE to hear my 0:38 demo recording, or HERE to see a video, or HERE to read an article with my lyric and accompanying commentary. 

* I wrote “Pi Will Go On” to the tune of Celine Dion’s biggest hit “My Heart Will Go On” (the song went to #1 all over the world as an all-time best-selling single) by Will Jennings and James Horner.  Rational numbers (e.g., ¼ = .25 or 1/6 = .16666….) have decimal expansions that end or go into a repeating pattern, but because pi was proven to be irrational, its decimal representation “will go on”, which inspired me to revise the song from the 1997 blockbuster film Titanic. Click HERE to hear my 2:31 demo recording, or HERE to read an article with my lyric and accompanying commentary.

my favorite pi songs by others: (also, see ; ; ; ;

Pi Day Haiku (some say “pi-ku”): I was announced by “Math Matters at Taylor & Francis” social media on 4/8/15 as a winner of its 2015 Pi Day (of the Century) haiku contest for my entry, which I later published in on p. 456 of


Pi cartoon:


Teacher ARTICLES: See my 6-page article “Slices of Pi: Rounding Up Ideas for Celebrating Pi Day” in the fall 2004 Texas Mathematics Teacher. Also of interest is Sandra A. Daire’s Pi Day article “Celebrating Mathematics All Year ‘Round” in the March 2010 Mathematics Teacher, 103(7), 509-513. Also, teachers interested in culturally relevant mathematics will appreciate my article in The Jewish Educator and the “value of pi” section of my article in Journal of Mathematics and Culture.

classroom activity: my “A Round This Date in Time; Pizza Pi, Anyone?” Cartoon Corner [with 9 classroom-ready discussion questions on 2 FoxTrot comic strips] in the March 2007 Mathematics Teaching in the Middle School, 12(7), pp. 383, 387.

RESEARCHER ARTICLE I co-wrote about family math nights which featured pi activities: “Parent Power Nights: A Vehicle for Engaging Adults/Families in Learning Mathematics” in the Nov. 2008 Adults Learning Mathematics International Journal, 3(2b), 36-52. 


Pi Day Local Outreach:  I’ve helped with pi day events for elementary school students (e.g., Canutillo ES; see, for example, the article starting on p. 36 of thismiddle school students (e.g., Henderson MS, as on p. 13 of this; a grades 1-8 school (see this), high school students (e.g., Emery HS in Houston; see article in fall 2004 Texas Mathematics Teacher), and college students (e.g., with UTEP’s undergraduate math club, Club Zero: see, for example, the last page of this).

pi-pourri of other links:


Interviewed on 3/14/19 by Louie Saenz, “Focus on Campus”, aired 3/15/19 10-10:16am, regional NPR-station KTEP

(88.5 FM):

UTEP social media posts on March 14, 2018 & 2017 such as:

Herrera, Valerie (2015, April 7). Professor wins pi day of the century contest. The Prospector, 100(23), 9.


Cohen, Cindy Graff (2015, April). Larry Lesser wins ‘Pi Day of the Century’ song contest. The Jewish Voice, p. 14.

Masterson, Veronique (2015, March 20). [story on my winning national pi day song contest was the closing

(and longest) story that week] UTEP Headlines Video Newscast,

UTEP News (2015, March 16). Math song wins on pi day of the century. (2015, March 14, 3:14pm). 2:38 video posted of me explaining Pi Day

Lopez, Meghan (2015, March 14, 9:10pm). KFOX-TV newscast, with online story by Adriana

Candelaria posted at

Rodriguez, Ashlie (2015, March 14, at 5:14pm, 6:09pm, 10:09pm). ABC-affiliate KVIA-TV newscast

Wadsworth, Ford (2015, March 22-28). Pi news [Whispers column]. El Paso Inc., 21(30), 7A.

Martinez, Aaron (2015, March 15). UTEP professor wins songwriting contest [18 column inches]. El Paso

Times, 135(74), B1. [story also appeared online at the day before with same text but with different headline]

Lopez, Meghan (2015, March 14, 10:15pm). CBS-affiliate KDBC-TV newscast, with online story by

Adriana Candelaria posted at

“El Paso Jewish Academy to Celebrate its First Pi Day!” (2008, April). The Jewish Voice, p. 19.

“Pi x 300 years = fun for Canutillo students” (2006, March 3). El Paso Times, 126(62), p. B6 West.

“Celebrating Pi” (2006, March 15). UTEP Horizons Online News, Que Pasa.

“Pi Day” segment (including interview with me) from Canutillo ES on 10pm newscast on El Paso’s CBS-affiliate

KDBC-TV on March 1, 2006; also, on El Paso’s KINT-TV (Univision, Channel 26).

“Henderson Middle” (2005, June), El Paso PROPS Magazine, p. 15

“Pi Day Celebration” (2005, May), Newsletter of Greater El Paso Council of Teachers of Mathematics, 4(5), 1-2.