A simple feedback tool that encourages collaboration when it comes to peer assessment. Provide students with a 4 box feedback grid and get them to compare work, then provide one another with feedback from 4 different peers. This can be varied by focusing on a particular skill or assessment objective, or by suggesting 4 different pieces of advice for a model answer. Another variation could be to use each box to challenge them to ABC (add, build on or challenge) their response. Students then act on this feedback and rewrite a focused part of the work.