This study examined differences in the composition processes used by educationally at-risk males and females who wrote essays as part of a high-school equivalency examination. Over 30,000 individuals were assessed taking 12 forms of the examination’s language arts writing section in 23 US states. Writing processes were inferred using features extracted from keystroke logs and aggregated into seven composite indictors. Results showed females to earn higher essay and total language arts writing scores than males, but only by trivial amounts. More pertinent was that, after controlling for language arts writing score, age, and essay prompt, all seven process indicators showed nontrivial, statistically significant differences, the most notable being for indicators related to fluency and different aspects of editing. The study’s findings are consistent in important ways with those from other investigations of school-age students and adults, and with results from both online and paper-based writing tasks. Implications are offered for conducting similar research for individuals composing in character-based languages like Chinese.