Hi, I was assigned to review your lesson plan. It was an excellent idea to split your class into two, UK and China, and have students discuss and present their findings and opinions. Students surely could learn more by simulating actual discussions than just reading materials. Only thing I have noticed was the size of the 2 groups. I usually make a group of 3 or 4, then give each group slightly different topics to discuss about. Otherwise there are always some students left out and not to engage in any activities in class. Again I am a Foreign Langauge teacher so the situation could be different, but if you could give a smaller group each phase of an time period and have each group to present their phases in chronological order, while the rest fill out with a Worksheet? or have them post their findings/opinions to your blog site like we do with this USC US-China website?
Have a nice summer.