This document provides instructions for a lesson on peer assessing coursework using a construction mark scheme. The objectives are to gain confidence in understanding the construction mark scheme and to practice peer assessing other students' work. Students complete quizzes to test their knowledge of the assessment objectives and grade levels. They then peer assess video projects from other groups, assigning sublevels and an overall grade based on the assessment criteria. A plenary session follows to discuss progress made towards targets and confidence in applying the mark scheme.