A step-by-step method of teaching the X-ray diffraction analysis of DNA using the approach employed by James Watson, Francis Crick, Maurice Wilkins, Rosalind Franklin, and Raymond Gosling at an upper undergraduate and graduate level is described. This method includes a historical account of the 1953 articles by James Watson and Francis Crick, Maurice Wilkins et al., and Rosalind Franklin et al. Throughout the X-ray diffraction analysis, excerpts of their articles are included to describe the obstacles encountered by these researchers, the contributions each person made to the determination of the structure of DNA, and the degree to which X-ray diffraction aided their determination of the DNA structure. The article is organized with the assigned problem as the main part of the text and the intermediate steps leading to the solutions given in the Supplemental Material. Helpful hints and information are also given in the Supplemental Material. Writing the article in this way allows the project to be quickly implemented into upper-level undergraduate and graduate physics, chemistry, and materials science and engineering course curricula.