In October 1996, I founded, along with Dr. Gavin Hitchcock and Tawanda Gwena of the Mathematics Department at the University of Zimbabwe, a magazine aimed at high school students and teachers for popularizing mathematics. I wrote several articles for Zimaths, and was also involved in editing, typesetting, and placing the magazine online. My involvement with Zimaths ended in 1999 when I moved to the United States for graduate school. Unless otherwise mentioned, all articles below were written for Zimaths. Some of them are, in retrospect, cringeworthy, but ... live and learn.
April 2001: The Kepler Conjecture. Published in the MAA magazine Math Horizons. This article was chosen to appear in the compendium ``The Edge of the Universe: Celebrating 10 Years of Math Horizons'', edited by Deanna Haunsperger and Stephen Kennedy, Mathematical Association of America, July 2006.
Feb 1999 : The Three-Colour Problem. This article, regarding certain graph theory conjectures that I surveyed in my undergraduate B.Sc. Thesis, was published in the February 1999 issue of the Indian magazine Resonance. (PDF, see pages 76-81.)
Well I had to put this stuff somewhere (yeah, I wrote it.)