Due to the stipulations on the controlled assessment this is a very good way for students to provide feedback and receive feedback from each other. They will need to assess an exemplar, giving a mark out of 8, if using criteria 1 as the exemplar etc. They will need to give reasons fot the mark they assigned and say how the person could improve their work. They will then be shown the commentary from the teacher or the exam board to compare. They will then peer assess the work of someone in the class using a similar assessment sheet. I have attached one, feel free to make your own.
There are some very moving videos on the International day of peace website which goes very well with this assembly. Choose a video which will fit right in with your assembly time factoring it's length, the powerpoint and how long you intend to talk.
Giving children a chance to look at situations in which people might find themseves and letting them decide whether it is justice or should there be compassion. Getting them to think about situations and being able to decide on a fair actions and being able to conclude for themselves why things are as they are and decisions made, are as they have been.
With the new controlled assessment The AQA SOW is very clear about the things students need to know and to be taught. This is a lesson which provides all the information needed by students when learning about ideograms with a nice practical aspect. Please feel free to modify as you see fit.