The inclusion of writing is implicit within the expectations of the Common Core State Standards (CCSS) and Next Generation Science Standards (NGSS), particularly within the science and engineering practices component of the standards. NGSS goals include educating all students in science and engineering and providing the foundational knowledge for students who will become the scientists, engineers, technologists, and technicians of the future (National Research Council [NRC], 2012). However recent research points to numerous issues related to teachers' readiness to teach writing in science to a diverse group of students, including students with disabilities. According to a recent national survey, the majority of science teachers surveyed report not using evidence-based practices to teach writing in science class, nor are they using evidence-based adaptations regularly to support struggling writers (Drew, Olinghouse, Faggella-Luby, & Welsh, 2017). One solution to science teachers' lack of readiness to include writing in science to meet the CCSS and NGSS and the needs of all students in their classroom, including students with disabilities, is to work collaboratively to plan writing instruction with special education co-teachers. The WiS Co-Planning Tool is a research-based tool to help special educators and their science educator colleagues plan writing instruction to prioritize science content learning, meet the CCSS and NGSS, and support struggling writers and students with disabilities. As co-teaching teams use the WiS Co-Planning Tool, they plan four components to implement effective writing instruction in science (i.e., writing purposes, writing tasks, evidence-based practices for teaching writing, and additional adaptations to support students with disabilities). The tool was developed based on a synthesis of research for writing in science and the results of a national survey of science teachers (see Drew etal., 2017).