Analytical writing poses particularly challenging, yet often overlooked, language demands that need attention in educational research and practice. In this article, I discuss the Core Analytical Language Skills (CALS) construct and its relevance for school reading and writing. CALS refer to the set of learners’ school-relevant language resources that are of high utility to understanding analytical texts across content areas. After a brief review of the relations between mid-adolescents’ language and their school reading and writing proficiencies, I offer illustrative examples of individual differences in middle-schoolers’ analytical writing and CALS. I argue, on the basis of recent but extensive empirical evidence, that without understanding and addressing the immense variability in the language resources that students bring to school and the language demands of reading- and writing-to-learn tasks and texts, schools run the risk of maintaining and even exacerbating the inequalities that exist in the larger society.

Beyond mechanics and spelling conventions, academic writing requires progressive mastery of advanced language forms and functions. Pedagogically useful tools to assess such language features in adolescents’ writing, however, are not yet available. This study examines language predictors of writing quality in 51 persuasive essays produced by high school students attending a linguistically and ethnically diverse inner-city school in the Northeastern United States. Essays were scored for writing quality by a group of teachers, transcribed and analyzed to generate automated lexical and grammatical measures, and coded for discourse-level elements by researchers who were blind to essays’ writing quality scores. Regression analyses revealed that beyond the contribution of length and lexico-grammatical intricacy, the frequency of organizational markers and one particular type of epistemic stance marker (i.e., epistemic hedges) significantly predicted persuasive essays’ writing quality. Findings shed light on discourse elements relevant for the design of pedagogically informative assessment tools.