Content is related to other aspects of writing, but exactly how they are related has remained unclear or has not received sufficient critical attention. Consequently, in most writing assessments, content has been treated as just one among several relatively distinct but equal elements. However, in this study, the authors have quantified these relationships, and as a result can suggest, although this may seem controversial to many readers, that writing assessments may henceforth be simplified to assessments of content in cases where analysis of separate skills is not required. The data are stories written by children in English and scored by human readers or the Coh-Metrix. Three models of content were evaluated by using structural equation modeling. The model in which content is influenced either directly or indirectly by five writing elements--namely, vocabulary diversity, text length, coherence, originality, and grammar--provided a reasonable explanation of the data. The model shows that content can be defined as the sum of these five elements, which together explain content to a substantial extent. Since the substantial portion of content is the combined result of all these elements, we can simply assess content and know that, through their direct and indirect effects, content also represents all five textual elements.