Gary Christie graduated with a degree in mechanical engineering and worked for the Goodyear Tire & Rubber Co. for seven years designing new treads; he was a primary designer for the Aquatred tire earning several patents for this and other work. He returned to school to become a high school mathematics teacher teaching at three different districts before returning to college to earn a Ph.D. in curriculum & instruction with an emphasis on mathematics education. Gary has since worked at 91快活林 as a professor of education with an interest in conceptual mathematics.