I have lived in San Antonio since I was 15 years old.  I attended high school at San Antonio Christian School, where I graduated in 1994. I then attended college at Texas A&M University, where I graduated in 1998 with a degree in Applied Mathematics. This is my twenty-fourth year teaching - I taught at Roosevelt my first year, then I was at Madison for three years, and now I am at Churchill for my twentieth year. 

My main hobby is origami - At the same time I began teaching, I also started to practice the art of paper folding.  Over the years, I have gained the ability to fold super-complex models from a single uncut square of paper, which is known as "pure" origami.  I have also learned to design my own original models by studying the mathematical principles in Robert Lang's book Origami Design Secrets.  If you would like to see pictures of my work, visit my personal website:  derek.mcgann.com.  Through the process of learning technical origami design, I have applied some of the trigonometry I teach in Pre-Calculus to constructing base crease patterns which I then use to fold original origami creations.  I have written two articles on this process, both of which have been published on the OrigamiUSA website:

1.  Origami Flower Design - This article deals specifically with the use of right triangle trigonometry in the construction of radial crease patterns that I have used to create a few specific origami flowers. This was kind of a one-time puzzle I was interested in solving and does not represent what I do on a regular basis to construct the majority of my designs.

2.  A General Approach to Crease Pattern Construction - This article deals with the construction of more various types of crease patterns, using non-right triangle trigonometry as well.  This outlines the process I have come to use for almost all of my original designs.