One crucial part of education is teaching students to critically evaluate and reflect on their work. Oneway to perform this is through peer review and self-assessment. In this research paper, we present theresults of a longitudinal study over five years with 239 students following the implementation andevaluation of peer review and self-assessment. Using qualitative and quantitative analysis, we exploredifferent types of self-assessment, the benefits of incorporating self-assessment into the learningprocess, and lessons learnt during the years. Results show that students appreciate assessing their ownand others’ work. The students in the study are very good at evaluating their capabilities, the differencebetween the self-assessment and teachers’ final assessment was about 10%. With a studio-basedapproach, with formative feedback throughout the process, individual oral and written presentations andsupport from self-assessment, team feedback and teacher discussions, there is a much higher certaintythat students are assessed accurately.