The Peace Rose is a Montessori classroom tool/resource that is used to problem solve peacefully in a social conflict. The children that are involved are asked to go to the peace table where they will find a peace rose. They will then take turns talking about how they are feeling, and come up with a peaceful solution before returning to play.
There is a wonderful story that goes along with this tool, that can be read to the class to help enforce the idea of the tool within your classroom enviroment.