As students and teachers embrace more forms of multimodal composing, classroom power structures move from the more linear, hierarchical structures typically seen in education to more open, student-centered forms. However, these transitions are not always seamless. Using a multiliteracies framework, this article focuses on how a classroom teacher framed what counted as writing in a senior English class where students created a digital writing portfolio across three platforms. Findings explore what counted as writing from the perspective of the teacher before, during, and after the portfolio unit as well as the struggles that she faced in understanding how to assess the myriad of possible authoring paths multimodal projects offer. Implications extend to how teachers may be influenced by and continue to push back on established institutional power structures to open spaces for reshaping what counts as writing in the classroom.