While marking rubrics offer a range of potential benefits for students and staff, educators are working to develop a richer understanding of the most effective ways to unlock these benefits. This study contributes by examining the link between rubrics and performance through the lens of student engagement. The work introduced an assessment rubric and examined student grades across three conditions: i) when students do/do not have the marking rubric, ii) when students do/do not engage with a discussion about how and why to use the rubric, and iii) when students do/do not engage with the rubric discussion plus additional resources. The results indicate that simply providing a rubric does not necessarily lift student performance whereas higher grades are evident when students engage with discussing the rubric. Further analysis showed that grades were ever higher when students engaged with the rubric discussion plus additional resources. The findings have practical implications for effectively using rubrics and fostering improved performance through student engagement.