This three-manuscript dissertation-in-practice explores the opportunity gap in literacy between multilingual and monolingual English-speaking students in an elementary school located in the Northwestern United States. The first manuscript provides a final diagnosis of the problem based on findings from literature and needs assessments in my organization. It also discusses factors that cause and maintain the problem as well as possible solutions. Manuscript Two builds on the knowledge gained in Manuscript One with a detailed discussion of a mixed methods study where one of the solutions proposed in Manuscript One was tested using a Plan, Do, Study, Act (PDSA) cycle. This study focused on the impact of structured co-planning between the English Language Development Teacher (ELD) and classroom teachers on their multilingual self-efficacy after being trained to use the McDonald et al. (2013) protocol of Looking at Student Work (with Equity in Mind). The research questions focused on the effects of this structured co-planning on teachers' self-efficacy and their lived experiences during this study. Findings suggested an overall increase of 6% in teachers' self-efficacy and the seven themes that emerged from qualitative data addressed both research questions. Manuscript Three is in the form of a policy brief in which an executive summary is provided followed by a brief overview of the findings and recommendations for educational leaders based on these research findings. A conclusion of what I learned about this problem of practice and how I changed as a leader through my doctoral journey concludes my dissertation in practice. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]