Stephen Chu teaches in the mathematics department, and in the city semester program at Ethical Culture Fieldston School in the Bronx, NY. He received his undergraduate degree in mathematics from Columbia College and graduate degrees from the Courant Institute at NYU and Stony Brook University. He spent a few years working in the financial sector with asset backed securities before deciding to become a teacher. KSI was a wonderful formative experience early in his teaching career, and he is excited to be a part of the program once more.