The Adventure of Teaching Algebra

This one-day workshop was organized by the Texas Valley Communities Foundation and the Texas Graduate Center, which is affiliated with the Math for teaching degree program at the Harvard extension school. Thanks to Mary Alice Reyes and Adriana Lopez from the Texas Graduate Center for arranging and organizing that (and dinner). It was an inspiring workshop with amazing contributions from the class which I still have to digest. There were almost 30 teachers present. (Photos by the center: pic1, pic2, pic3.) Some handouts are to the right. In the wake of the preparations, I also mixed in a bit of algebra in my current passion for geometry on graphs. Notes [PDF], Warm up [PDF], Unit 1 [PDF], Unit 2 [PDF], Unit 3 [PDF],Unit 4 [PDF], Postscript [PDF]. Feb 3, 2017: Hidden figures shows the importance of algebra skills:

More about the math. See also 10-2=20 [Jun 2, 2017] and Percentages [Jun 13, 2017].
Leonard Euler who lived from 1707 to 1783 is the grand master of Pedagogy in the realm of algebra. Euler also invented graph theory (Koenigsberg Bridge Problem), seeds of topology (Euler characteristic etc) and so many other things. He is probably the most inspiring mathematician ever, not only because of his theorems and formulas v-e+f=2,exp(i π)+1=0,1+1/4+1/9+1/16+...=π2/6 etc), but also because of his outreach and his passion for making it accessible. Euler walked the talk, like many of the teachers who throw their energy into the noble cause of teaching. Euler's contributions to algebra pedagogy was not only in writing his textbook in Algebra but producing a gold standard in clarity which is hard to surpass. It is one of the most successful textbooks of all times.
I have here PDF files of Euler's Algebra textbook:
English translation [PDF] (with notes of Bernoulli and Lagrange) German Part I [PDF], German Part II [PDF]
The textbook is quite small as can be seen on this page from 2006. Some blog notes about addition and multiplication, on networks. This topic got mentioned at the end of this workshop illustrating that basic discoveries in arithmetic are not over (we have barely scratched the surface!)
The picture to the right was taken in my Office. It is part of this panorama. To the left (click for more photos), we see the "Fraction lab".
Some photos from the workshop. I hope to link later to more, done by the graduate center.
There is also great food in the Texas valley. Here is a photo from a restaurant (thanks to Claudia from the Texas Valley Communities Foundation) for that lunch:

The Renaissance hotel
Some pictures from an early morning run:

And from the McAllen airport featuring a Brother Wright type flyer (a replica close to Flyer III from 1905 or Model AB from 1910)
And while flying back, the magical Chicago O'Hare Airport tunnel connecting B and C. Oliver Knill, January, 20 2017,