Writing is a critical skill to develop, but many students are not proficient writers. Limited research exists about writing interventions, particularly interventions that are resource-efficient (e.g., provided by non-educators and in a small-group format) and can be used during early elementary school. This study evaluated an evidence-based writing intervention that was implemented by paraprofessionals with small groups of second-grade students with writing difficulties. Using a multiple-baseline design, participants' performance was assessed with six different writing measures. Findings showed that participants made promising improvements in writing quality and production, inconsistent improvements in story elements, and minimal improvements in curriculum-based measures of writing (e.g., correct writing sequences). Data evidenced sound social validity and usability for the intervention. Limitations, future research directions, and implications are discussed in terms of developing and delivering resource-efficient writing interventions, as well as challenges with monitoring students' progress in writing.