Two perspectives of the term "Venn diagram" reflect the typical differences in the uses of Venn diagrams in the subject areas of mathematics and language arts. These differences are subtle; nevertheless, they can potentially be confusing. In language arts, the circles in a Venn diagram typically represent things that can be compared and contrasted. For example, the items could be characters in a story, philosophies of teaching, or classes of animals. In this usage, the "characteristics" are placed in the circles, with characteristics that both share placed in the overlapping portion of the circles and characteristics unique to one placed in the nonoverlapping portion of the appropriate circle. This serves to highlight similarities and dissimilarities of the items being compared. In contrast, in the subject area of mathematics, the circles typically represent not "things" but their attributes or characteristics. The things are typically mathematical objects, such as numbers or geometric figures. The objects themselves, or representations of the objects, are placed in the circles instead of characteristics of the objects being placed in the circles. In this case, the Venn diagram is used to sort the objects into sets, or in other words, to classify the objects according to whether they possess the characteristics represented by the circles. To investigate whether elementary school students have ideas about Venn diagrams similar to those presented in this article, the authors asked a fourth-grade class four questions involving Venn diagrams and followed these questions with the Ring Labels activity (NCTM 2001). Based on the results of their investigation, they conclude with a number of recommendations for elementary school teachers in using Venn diagrams with their students. A bibliography is included.