This material is a description of the peer assessment intervention in the dissertation of Ketonen (2021). The intervention comprises both training and practice of peer assessment. It lasted 1,5 years and it was implemented in physics and chemistry on grades 7-8 during the years 2018-2019. The material is described in the order of the implementation. The intervention was built on previous research on peer assessment. The material functions as an example of how training and practice of peer assessment can be used as a part of subject learning in Basic Education.

2021