I decided to give them something less emotionally charged than arguments from their classmates. My original plan was to buy some Japanese magazines so that the students could choose the ads that they were interested in. I abandoned that idea after I found it very difficult to choose suitable magazine content.
Instead, I chose some inserts from the newspaper, all in Japanese, all touting easily identifiable products or services.
I gave them a brief lesson on Aristotle's Ethos, Logos, and Pathos, and then let each group of 3 students choose one of the inserts to descent.
There were several different advertisements to choose from. The easiest ones to use seemed to be those selling nutritional supplements, pachinko, restaurants, and electric appliances. My students were not interested in the pachinko advertisements.
After finishing with the Japanese advertisements, I gave them magazines written in English so that they could search for an ad about which they could discern the Ethos, Logos, and Pathos, based mostly on the images rather than having to rely on the meaning of words.
This activity worked well, and the students got some practice taking apart arguments using language, and those using predominantly images. Next we will have to try to examine verbal arguments from others in the same way.