In the introduction to this site we learn that, "A fundamental result of geometry, used often in secondary and collegiate mathematics, is the equality of ratios of corresponding sides in similar triangles." Accordingly, this concept is expected knowledge of students in physics, engineering, and the sciences, "since its simple statement is rather useful in finding unknown lengths of elementary figures in plane geometry." Recently, Professor Jerry Lodder of New Mexico State University decided to explore how similarity theorems might be best used in the math classroom. This article offered here contains a set of curricular materials that draws on the ancient Chinese principle of area known as the inclusion-exclusion principle. Educators can use these resources to craft a discussion that includes a cross-cultural comparison of these concepts, and then draw on the student exercises that are also included in this piece.