Seeing through the crowds: How to analyze a riot

So far, my new Advanced Higher class have been thinking about the Geographical Study, the part of their portfolio which involves independent fieldwork. I have previously been guilty of giving this less prominence early in the course as we tried to equip classes with the techniques that they would need for field study, and am pleased that topics are in place for most candidates already. With that in mind, we are changing direction tomorrow as I focus on Geographical Issues. I'm planning on using current events as a trigger again, just as we did with local issues surrounding the school when introducing how to conduct fieldwork around a hypothesis. This time, I'm going to look at the London riots.
I realise that the riots have split opinion with regards to their cause(s), and a number of colleagues directed me to some incredibly biased reporting of events. I have my own strong views on this, but am stepping back from this to see a) whether students can make decisions based on the strength of evidence and argument and b) whether any actually conclude that a source at odds with their own opinion might actually present the most convincing case.
This link is a good starting point for a variety of different perspectives on the riots, but I'd rather discuss our way in to the topic by seeing what students perceptions of the riots and rioters are. Afterwards, we will take one of the articles and, after a brief read, discuss the merits of the authors argument. At this point I will probably play devils advocate to opinion presented as fact, bias presented as authoritative and will try to encourage students to look beyond the words to, for instance, the author, the target audience and more. After this, we will spend some time using Russel Tarr's source analyzer for some of the other articles.
In as much as this is not entirely geographical, it will introduce early in the course key skills of critical evaluation. The geographical issues element of the course is worth 30% in marks but, in my opinion, worth a lot more in developing transferable skills which will help the students beyond their school careers.