The Actionable Assessment project sought to improve the quality of the student assessment experience by designing and testing a digital reporting tool that engaged students in interpreting and using assessment results to foster their own learning. The tool was designed within the ONPAR assessment system which contains dynamic online science tasks for middle school students. ONPAR's unique task design facilitates accessibility for students who struggle with text-heavy traditional tests such as English learners and developing readers and yet works equally well for general education students. The Actionable Assessment reporting tool aims to help make students' assessment results interpretable and actionable and foster positive assessment use and learning habits. This article provides an overview of the design process and pilot results from three iterations of the reports in classrooms. A learning engineering approach provides insight into the reporting tool's effectiveness at engaging students in reflection and plans for learning.